Organizational Genealogies and the Persistence of Gender Hierarchies: Silicon Valley Law Firms, 1970 to 1996.*

Damon J. Phillips Associate Professor of Organizations and Strategy

University of Chicago, GSB Chicago, IL 60637

damon.phillips@gsb.uchicago.edu

ABSTRACT

I propose an organizational theory on the genealogical persistence of gender hierarchies that uses insights from organizational imprinting (e.g., Stinchcombe 1965) and gender hierarchies in groups (e.g., Ridgeway 1997) to extend recent research on organizational genealogies (Phillips 2002). I argue that founders replicate the gender hierarchies of their parent firms. Founders from firms that historically lacked women in high-ranked positions are less likely to place women in positions of power within their own firms – independent of the degree of direct contact with high-ranked women. Rather, it is founders from firms that historically have women in prominent positions that are more likely to start firms that in turn hire and promote women into prominent positions. Similarly, founders from firms that historically have women in subordinate positions are less likely to hire or promote women into prominent positions. Also consistent with the theory is the finding that the persistence effect is stronger for founders who were previously lower-ranked employees. Using data on male-founded Silicon Valley law firms, findings support the theory while controlling for several alternative explanations. Supplemental analysis suggests that gender hierarchies may in part be transferred within a set of routines.

* I would like to thank the participants in the Organizations and Markets workshop and the MOB brownbag at the University of Chicago GSB, as well as the participants of the organizations seminar at the Yale School of Management.

INTRODUCTION

At the intersection of research on organizations and gender inequality sits a substantial

body of work on the role that organizations play in creating, sustaining, and altering

differences in attainment between men and women (Baron 1984). Indeed, employment

settings are one of the primary structural arrangements that recreate ordinal status

rankings of individuals by gender – referred to as gender hierarchies (Ridgeway 1997).

Whether the outcome is hiring (Fernandez and Sosa 2003), wages (Madigan and Hoover

1986; Kilbourne, et. al. 1994; Hersch and Viscusi 1996), promotions (Olsen and Becker

1983; Cannings 1988; Lazear and Rosen 1990; Jones and Makepeace 1996), or turnover

(Spurr and Sueyosji 1994), scholars have often found that women are disadvantaged

within organizations. Not surprisingly, attention to gender inequality extends beyond

academia to include members of the popular press (Miller and Friday 1992; Seligman

2001) and business leadership community (Gordon and Whelan 1998).

Despite the vast interest and research in this area, less is understood about the structural

antecedents of gender hierarchies within organizations. Specifically, we know little

about the relationship between founding conditions and subsequent employment and

promotion opportunities for women. Indeed, research within this area is just emerging

(Baron, Hannan, Hsu, and Kocak 2002). At the same time, this new focus is rife with

potential, as it allows us to not only determine the conditions under which gender

inequality emerges in new organizations, but to also improve our understanding of the

persistence of gender inequality across generations of organizations.

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Drawing upon Stinchcombe’s (1965) attention to organizational imprinting, sociological

research on groups by “microinstitutionalists” (Zucker 1977; Lucas 2003), and a

genealogical approach to organizational populations (Phillips 2002), I propose an

organizational theory of gender inequality that emphasizes the routines (or blueprints)

that founders transfer from parent firms to their new firms. This transfer of routines

reproduces the parent firm’s demographic composition in the new firm. Founders from

firms that historically lacked women in high-ranked positions are less likely to place

women in positions of power within their new firms. In other words, founders from

parent firms that historically had women in subordinate positions (where female

subordination is institutionalized) are less likely to hire or promote women into high-

ranked positions. At the same time, founders from parent firms that historically had

women in high-ranked positions (where female leadership is institutionalized) are more

likely to start firms that hire and promote women into high-ranked positions.

I investigate the persistence of gender inequality using data on 35 years of Silicon Valley

law firm startups that capture the gender composition of law firm progeny and their

parent firms. I hypothesize and find that (ceteris paribus) progeny firms are more likely

to place women in partnership positions to the extent that the progeny’s founders came

from firms that historically had women partners. At the same time, progeny firms are

less likely to place women in partnership positions to the extent that the progeny’s

founders came from firms that historically had women associates (ceteris paribus).

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I consider these findings alongside two alternative explanations. First, I insure that my

findings are not caused by direct contact with women in parent firms – as Allport’s

(1954) seminal research may suggest (see also Cook 1985; Pettigrew 1998). If my thesis

is correct, founders will replicate the gender hierarchy independent of the degree of direct

contact with women in the parent firm. A parent firm that has had a woman partner for

the first nine of its ten years of existence is more likely to have progeny that will promote

women to partner, even if a progeny’s firm founder worked in the only year in which

there was no woman partner.

A second alternative posits that intergenerational persistence of gender hierarchies occur

when key decision-makers in the parent firm leave to replicate a similar structure in the

progeny firm. In other words, social structures are replicated because the same

individuals that established the opportunity structures in the parent firm also construct the

opportunity structures in the new firm. This alternative suggests that there would be no

replication of the parent’s gender hierarchy by founders who were not decision makers in

the parent firm. On the contrary, I will argue that the lower-ranked, non-decision-making

personnel are more likely to assume a parent’s demographic composition as objectified

fact (Berger and Luckman 1967). This yields an opposite conclusion: lower ranked

employees are more likely to replicate the gender hierarchy of the parent firm than are

higher-ranked employees. Thus, after testing the initial hypotheses, I will examine

whether these effects are greater when the founder was former a lower-ranked employee.

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The implications of this research present a promising contribution to the literature. In

general, an organizational genealogy framework not only suggests ramifications for the

fate of the parent organization and its offspring (Phillips 2002), but also on the

intergenerational variation and persistence of organizational opportunity structures. As

founders leave their parent organizations, the organizational models they carry with them

reproduce the set of employment opportunities and constraints faced by employees in the

parent firm. In other words, the intergenerational diffusion of employment practices may

contribute to the persistence of sex segregation within organizations.

BACKGROUND AND THEORY

Among the key contributions of Stinchcombe (1965) is that organizational structure is

influenced by conditions that existed at the time of an organization’s founding (see also

Kimberly 1979). Components of organizational environments are “imprinted” on the

structure of new organizations. This insight has influenced many veins of research within

organizational sociology, but few more than population ecology and neo-institutional

theory, whose adherents have shown that not only do exogenous forces influence the

strategy, structure, and vitality of organizations (Meyer and Rowan 1977; Carroll and

Delacroix 1982; DiMaggio and Powell 1983; Swaminathan 1996; Hannan 1998), but so

do those founding conditions which are more endogenous to an organizational population

(Carroll and Hannan 1989; Tucker, Singh and Meinhard 1990). To the extent that we

understand founding conditions, we are better able to understand the emergence and

persistence of an organization’s structure and set of routines. Moreover, since an

organization’s structure at founding substantially influences structure and action later in

the life course of the organization (Stinchcombe 1965; Boeker 1989; Baron, Hannan and

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Burton 1999), Stinchcombe’s insight becomes an important lens for understanding

organizational structure well beyond the organization’s founding.

While Stinchcombe (1965) draws attention to macro-institutional forces (he uses

examples that contrast organizational forms before and after major societal events such as

the rise of the Soviet Union, the Industrial Revolution, and the Meiji Restoration in

Japan, pp.153-155), I draw attention to the role of micro-institutional forces (Zucker

1977) that lead to imprinting. My motivation is twofold. First, recent research suggests

that to the extent that macro-institutional forces can be isolated, there remains substantial

variation in a cohort’s organizational structure, strategy, and template for the organization

of work (Baron, Hannan and Burton 1999). Second, there is an established literature

demonstrating that given an organization’s structure at founding, there is remarkable

resilience of that structure over time (Meyer and Scott 1983; Hannan and Freeman 1984;

Boeker 1989). My general interest is in examining the factors that constrain founders in

their choice of organizational blueprints.

In understanding the persistence of gender hierarchies across generations of

organizations, I incorporate “micro-institutionalist” research on the transmission and

maintenance of organizational routines (Zucker 1977; also see Levitt and March’s 1988

discussion on organizational memory) with research on organizational genealogies

(Aldrich and Pfeffer 1976; Freeman 1986; Phillips 2002). In particular, I anchor my

model of an intergenerational persistence of gender hierarchies on Phillips’ (2002)

argument that organizations (progeny organizations) often arise as founders leave

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existing organizations (parent organizations), transferring some of the parent’s routines to

the progeny organization. As a consequence, the structure and the culture of progeny

organizations is in part determined by the structure and culture of their parent

organization. Thus, when examining organizational progeny as proliferators of gender

hierarchies, the parent organization’s routines must be included among the set of initial

conditions that influences a progeny’s tendency to place women in high-ranking

positions.

The parent-progeny transfer of routines that affect gender hierarchies conceptually falls

into two categories. First are routines that are transferred by the founder as formal rules

(Dutton and Starbuck 1978; Nelson and Winter 1982; Baron, Hannan and Burton 1999) –

although they need not be transferred specifically to affect the fate of women employees.

Examples of formal rules are recruitment and evaluation policies, as well as other rules

that dictate the organization of work (e.g., written job descriptions, policies on flexible

work arrangements) (Baron, Hannan and Burton 1999; Fernandez and Sosa 2003). Other

formal, but less direct rules and routines may also include a set of rituals introduced by a

founder to achieve a particular level of employee commitment and cohesion (Schein

1992). All-in-all, this suggests that founders may rewrite the parent’s gender hierarchy

into their new organization through formal rules.

A second category of routines includes “taken-for-granted” rules or interpretations of

legitimate action that founders (perhaps unwittingly) draw from their past organizational

experiences. This category of routines builds upon multiple studies by scholars in the

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status construction vein (Markovsky, Smith and Berger 1984; Ridgeway and Smith-

Lovin 1999; Ridgeway and Erickson 2000) and recent evidence provided by Lucas

(2003). Using a laboratory setting, Lucas (2003) found that when group members learn

that “successful groups have women as leaders, and when members see that groups

similar to their own have women in leadership positions … female leaders had as much

influence as did male leaders with comparable ability …” In my context, some founders

leave a parent firm in which female leadership is institutionalized. The fact that female

leadership was institutionalized in the parent makes the founder more likely to view

female leadership positively. Ridgeway and Erickson’s (2000) research supports this

contention. Their work demonstrates that beliefs about status hierarchies, once

established, can be spread to others as individuals enact learned beliefs about the relative

status of women and men even as they enter a new context. As a consequence, gender

hierarchy is transferred from the parent to its offspring through the actions of the founder

and those whom that founder “teaches”. Finally, while a founder’s beliefs may be

explicitly stated, it need not be. In fact, Zucker’s (1977) and Lucas’ (2003) work

suggests that founders may never question their views on gender and leadership.

The focus on the transfer of routines, both explicit and taken-for-granted, places this

theory in an agnostic position when it comes to the psychological antecedents of gender

inequality across organizational generations. That is, it may very well be that among the

routines and beliefs transferred is an overt bias against women leaders. However, it may

also be the case that by transferring particular employment models to a new firm (e.g., an

employment model that emphasizes commitment to the employer), the founder may be

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influencing the present and future demographic composition in ways that are unpredicted

and unintended.

HYPOTHESIZING THE TRANSFER OF GENDER HIERARCHIES

I test my theory by focusing on the degree to which female leadership and subordination

(location in a gender hierarchy) is institutionalized in a parent organization. Ceteris

paribus, founders from parent organizations that have a long history of women in high-

ranked positions are more likely to have high-ranking women in their own organizations

(either by promotion from within or hiring from the external labor market). These

founders transfer routines that facilitate the advancement of women. Capturing the

history of women in high-ranked positions by the proportion of years over a parent’s life

cycle that women have been high-ranked, I hypothesize,

H1 (Institutionalized Female Leadership): Ceteris paribus, the more years over its life-cycle that a parent organization has women in high-ranked positions, the greater the likelihood that its organizational progeny will place a woman in a high-ranked position. A more subtle prediction, but one that is consistent with the framework, is that founders

from parent organizations that have a long history of women in lower-ranked positions

are less likely to have high-ranking women in their own organizations. That is, holding

the representation of women in high-ranked positions constant, the more the parent

organization is characterized as having women in lower-ranked positions, the lower the

likelihood that departing founders will place women in high-ranked positions. Similar to

the argument for H1, having a history of women in subordinate positions increases the

chances that founders carry with them formal and taken-for-granted routines that

replicate women’s subordination.

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H2 (Institutionalized Female Subordination): Ceteris paribus, the more years over its life-cycle that a parent organization has women in low-ranked positions, the lower the likelihood that its organizational progeny will place a woman in a high-ranked position.

With Hypothesis 2, I am suggesting that having a long-history of women in subordinate

positions has a greater negative effect on the attainment of women in the new firm than if

there were no women at all in the parent firm. In this way, H2 is a powerful test of the

conceptual model, with an interesting implication: women have a higher chance of

making partner in a law firm when the founder came from a firm with no women,

compared to a firm in which women were consistently in subordinate positions.

Finally, there should be differences in the hypothesized effects based upon the former

position of the founder. Lower-ranked members should be more prone to recreate the

gender hierarchy because it is more likely to be seen as an objectified reality (Berger and

Luckman 1967; Zucker 1977). Especially for lower-ranked members with little labor

market experience outside of the parent firm (which is the case in my data), the parent’s

organizational blueprint lacks any competing alternative. This ignorance enhances the

taken-for-granted gender hierarchy of the parent firm.

This prediction is consistent with a long tradition of research shows that individuals that

value membership into in a group yet feel insecure in that membership (e.g., an associate

in a law firm) are more likely to embody the norms of that group (Dittes and Kelley

1956; Blau 1960; Homans 1961). In applying this particular line of reasoning, however,

suggests that the potential founder would be more aware of the transfer of routines from

the parent than an “objectified reality” explanation would emphasize. Nevertheless, both

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explanations lead to the same conclusion: former lower-ranked employees should be

more likely to replicate the institutionalized gender hierarchy of the parent firm.

H3a: The hypothesized effect in H1 (Institutionalized Female Leadership) should be greater when the founder was formerly a lower-ranked member of the parent firm. H3b: The hypothesized effect in H2 (Institutionalized Female Subordination) should be greater when the founder was formerly a lower-ranked member of the parent firm. While potentially there are several alternative explanations, at least two are critical. First,

it is possible that the parent and progeny are in a market position (or niche) that drives

particular patterns of gender hierarchy across generations, but independent of any

routines that are transferred from the parent firm. For example, in law firms one may

expect that women are disproportionately underrepresented in a particular area of law,

especially at the partnership level. In this case the fact that the gender hierarchy is

replicated from the parent to the progeny is driven more my the economics and social

dynamics associated with the type of service offered than by any parent firm-specific

routines transferred to the progeny law firm. While other empirical studies place doubt

on this alternative explanation (Chambliss 1997), I address this concern in two ways.

First, I control for different areas of practice. Second, I code the proportion of women

associates in the law firm when predicting the likelihood of a woman being placed in as a

partner. This will control for the extent to which the firm is in a market niche or area

over or underrepresented by women.

A second alternative builds upon Allport’s (1954) seminal work on discrimination. His

“social contact theory” suggested that discrimination against lower status minorities

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could be remedied if: (a) members of the majority could directly interact with the

discriminated member; (b) in a context where the two groups were of equal status; (c)

and were pursing a common goal; (d) through interdependent action. Extending this

logic, it is possible that departing founders who have directly interacted with women in

high-ranking positions are more likely to have women in high-ranking positions in their

new organizations (Lundberg and Startz 1983; Jackman and Crane 1986). Similarly,

founders with direct interactions with women in subordinate positions may be less likely

to place women in high-ranking positions in their own firms. In this second case, the

interaction would amplify any existing negative stereotypes about women.

To test this second alternative, I will control for the number of years each departing

founder worked in which there were women partners and associates, respectively. While

I lack the evidence to confirm actual interaction, it is likely that some form of interaction

would occur given that the organizations in my dataset are relatively small (the average

size of a parent law firm is 9.8 lawyers). Although I expect that Allport’s (1954) thesis

would be confirmed, the transfer of routines that affect women’s attainment in the new

firm should be independent of the direct interaction that the founder had in the parent

firm.

CONTEXT AND DATA Women’s Attainment in Private Practice Law Firms The attainment of women in law firms has received frequent scholarly attention (Epstein

1981; Halliday 1986; Donovan 1990; Spurr, 1990; Hagan and Kay 1995; Dixon and

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Seron 1995; Kay and Hagan 1998, 1999; Gorman 2004). This topic is among the few

that has engaged not only sociologists, but economists (Spurr 1990), and legal scholars

(Rhode 1988; Babcock et. al. 1996).

Interest in women’s movement into the partnership ranks of law firms is fueled by two

related factors. First, promotion to partner not only involves the greatest increase in

income within a law firm, but partnership includes membership to the professional elite

with access to substantial social and political capital (Nelson 1988). Moreover, women’s

attainment within law firms has larger societal ramifications for access and opportunities

(Hagan and Kay 1995). Accordingly, women’s occupancy of high-ranked positions in

law firms is used as one barometer of generalized gender inequality.

Second, interest remains unabated because the progress of women into the partnership

ranks has been slow (Mossman 1988; Abel 1989; Phillips and Beckman 2004). Although

there has been a substantial rise in the proportion of women law school students and law

firm associates, progress with respect to women promoted to partner has been

comparatively slower (Abel 1989; Abrahamson and Franklin 1986; Hagan and Kay 1995;

Hull and Nelson 2000). Women are less likely to be promoted than men (Spurr 1990;

Kay and Hagan 1998), and more likely to leave before the promotion decision (Spurr and

Sueyoshi 1994), even controlling for experience or human capital-based qualifications

(Nelson 1988; Phillips 2001). Many firms have yet to promote any women to the level of

partner. Differences between men’s and women’s promotion chances seem to remain

after taking into account women’s choice to leave before the promotion decision (Hull

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and Nelson 2000). In fact, there is some concern that evidence is pointing to a decline of

an already low proportion of women partners (Ziewacz 1996).

The Data: Silicon Valley Law Firms As part of a larger project on the population dynamics of law firms, I collected data from

the annual Martindale-Hubbell Law Directory from 1946 through 1996, for law firms and

attorneys in Silicon Valley, California. The directories list attorney and law firm

characteristics and, when followed across time, provide information on the life chances of

law firms and whether the founder was previously affiliated with another Silicon Valley

law firm. As Suchman (1993, 2000) and Escher and Morze (1998) noted, Silicon Valley

is a relatively self-contained market for legal services in Northern California, with scant

legal activity before World War II. Silicon Valley comprises the following ten cities:

Redwood City, Menlo Park, Palo Alto, Los Altos, Mountain View, Sunnyvale, Santa

Clara, Cupertino, Campbell, and San Jose. In 1946 the area had only six law partnerships.

By 1996, Silicon Valley hosted 209 law partnerships employing 2,375 active attorneys.

For each law firm, I coded its founding date (its first appearance in the directory) to

alleviate any left-censoring. In all, I collected data on 513 law partnerships across the

fifty years, which comprises every firm listed with more than one active attorney -- solo

practitioners were excluded because they cannot be parent firms and lack distinctive

hierarchical positions. Of these firms, 137, or 27 percent, were founded by attorneys who

had a previous affiliation with a Silicon Valley firm (i.e., law firm progeny).

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I test my hypotheses on a subset of these data, using the last twenty-six years (1970-

1996). The shorter observation period used in this study is driven by the fact that before

1973 there were no women partners in any of the firms in my sample. Accordingly, I

considered my risk set any law firm progeny founded after 1970.1 I also bounded the risk

set by only including law firms with all-male founders. This is to allow the cleanest test

of my theory. Not only would including women founders (who by definition would be

partners in the new firm) confound the measure statistically, but it would add another

consideration to an already complex conceptual framework. The differences by gender in

the response to the institutionalization of women in leadership and subordinate positions

is complex (Ely 1994; Lucas 2003), and thus set aside for future consideration. The

dataset used to test my hypotheses includes 99 progeny law firms (founded by men only)

at risk of placing a woman as a partner.2

Dependent Variable: Having a Woman in a Partner Position. I coded a dichotomous,

variable to capture whether or not a firm had a woman partner. Each firm is followed

annually until one of the firm’s partners is a woman. Sex of the attorney was determined

using first names, with any gender neutral name (e.g., Pat) classified as male. Although

there were no questions of partners with gender neutral names, there were associates for

which sex was unclear. When possible, sex was confirmed with photographs available

on the web or in local bar association membership photographs. The dependent variable

equals one for the firm-year in which there is a woman partner. When this occurs, the

firm exits the risk set. Mirroring the low occurrence of partnering a woman in other

1 In additional analyses, I varied the observation window from 1960-1996 to 1976-1996. None of the results presented here were altered by changes in the observation window. 2 In the discussion I do report supplementary analysis using data that included women founders.

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samples of law firms, only 16 of the 99 firms listed a woman as partner by 1996.3 Given

that the partnering of a woman was relatively uncommon in my data, and typically of

only one woman at a time, modeling a risk of a firm partnering a woman for the first time

is appropriate.

Independent Variable: Institutionalization of Gender Hierarchies from Parent Firms. I

consider female leadership to be institutionalized the greater the proportion of years that a

progeny firm’s parent had any women partners before an employee left to found a new

firm. This was coded by calculating the proportion of years that there was a woman

partner in the parent firm, beginning with the parent firm’s first year and ending with the

year that the founder departs. Using this scheme, progeny law firms with parents that

never had any women partners are coded as zero. A value of one is assigned to those

progeny of parents that have had women partners in each year of the parent firm’s

existence. Similarly, we coded the proportion of years that a parent firm has women

associates as an indicator of how institutionalized women in subordinate positions were.

Founder’s Former Rank

In general, law firms have two positions: associates and partners. Associates enter the

firm directly from law school or after a one-year judicial clerkship. They generally work

under the firm’s partners, who leverage the work of associates by hiring them at a given

salary and billing them out to the firm’s clients at multiples of that salary. Associates are

considered for promotion to partnership after a period in which they work under the

3 The rate of partnering a woman for all 333 firms in existence from 1970 to 1996 is lower than the percentage partnering a woman by male-founded progeny law firms. Only 14.7% of the 333 firm had made a woman a partner by 1996. In comparing this statistic with data from the ABA, there is an indicator that my sample is representative. 13% of national law firms had women partners in 1995 (A.B.A. Commission on Women in the Profession 1995).

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supervision of the partners, receive training, and exercise increasing responsibility

(Smigel, 1969; Nelson, 1988; Galanter and Palay, 1991). Those not promoted must leave

the firm (the “Cravath” or “up-or-out” promotion system). Partners own the firm and

share in its profits. The transition from associate to partner is generally accompanied by

increased income, as well as a new functional role within the firm. Partnership

encompasses several new tasks and responsibilities, emphasizing skills in firm

management that transcend the traditional tasks involved with practicing law as an

associate (Nelson, 1988).

To test hypotheses 3a and 3b, I constructed a variable that equals one if the founder was a

former associate, zero if the founder was a former partner. If the intergenerational

persistence of gender hierarchy is more salient for founders who were formerly lower-

ranked members of the parent firm (associates), interacting this term with each of the

institutionalization variables would yield an amplified effect. That is, former associates

should be affected by institutionalized woman leadership and subordination more than

former partners. If this interaction effect is not statistically significant, then former

associates (lower-ranked members) are no less likely to be influenced by the history of

gender hierarchy than former partners (higher-ranked members).

Controlling for Allport’s (1954) Social Contact Theory as an Alternative. As a proxy for

former contact with women at the partner and associate levels, I coded two variables.

The first captures the number of years the founder worked with women partners in the

parent firm. The second captures the number of years the founder worked with women

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associates in the parent firm. Allport’s (1954) thesis suggests that the greater the number

of years of social contact with women partners, the more likely that the founder will have

a woman partner in his own law firm. Conversely, previous contact with women

associates should make founders less likely to make a woman partner in their own law

firms.

Figures 1a and 1b illustrate the difference between the hypothesized institutionalization

indicator and the Allport social contact alternative. In each figure, a parent firm has a

woman promoted to a high-ranked position in the year five. Also, each example features

an employee that enters the firm in the 15th year and leaves in the 20th year to found a

new firm. The difference between figures 1a and 1b lies in the number of years that the

high-ranked woman remains in the organization. In figure 1a, the high-ranked woman

remains in the parent firm at least fifteen years. When the employee leaves to found a

new firm, the high-ranked woman is still a member of the parent firm. In this case, the

degree to which woman leadership is institutionalized is 0.75, since a woman was high-

ranked in 15 of the 20 years that the parent firm was in existence. Measuring Allport’s

alternative, the new employee had 5 years of direct interaction with the high-ranked

woman. In figure 1b, the high-ranked woman leaves after 5 years – well before the new

employee enters the firm. While the years of direct interaction is 0, the value of

institutionalized woman leadership is greater than zero, or 0.25 (5 years divided by 20

years). This indicates that although the new employee did not personally interact with

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the woman leader, any organizational routines that were associated with that woman’s

leadership position are transferred by the employee into the new firm that is founded.4

----------------------------------------

Put Figures 1a and 1b About Here

----------------------------------------

Additional Control Variables

I control for the possibility that attorneys (as future founders) seek firms with a particular

gender hierarchy, then leave to found firms with a similar hierarchy. This endogeneity

effect suggests that the informed choices of individual attorneys (e.g., founders who

promote women previously chose to work in firms where women were in leadership

positions) drive any results. Alternatively, I argue that founder choices and action are

framed by the parent firm’s social structure (Blum 1985). I address this alternative by

controlling for the proportion of lower- and higher-ranked women that existed in the year

that the future founder began their career. That is, I follow each founder back to the year

in which they entered the parent firm then record the proportion of women associates and

partners. If it is the case that founder sought particular gender hierarchies earlier in their

careers, then replicated the hierarchies in their newly founded firms, these controls should

explain away my hypothesized effects.

4 Figures 1a and 1b present illustrations to distinguish between the two effects, neither is presented as representative. In fact, situations similar to 1b occur less often in my data. Only 6% of the progeny feature founders that have a zero value of direct contact and a non-zero value of the level of institutionalized woman leadership transferred to the progeny firm.

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To capture any population-level time trend effects, I generated a count variable ranging

from 1 to 26, for each year of the observation period. I included the log transformation of

the time trend variable since this specification improved the fit of the models. Firm size

was operationalized in two ways: (1) the total number of full-time partners and (2) the

total number of full-time associates. Given that the distribution of firm sizes was log-

normal (skewed to reflect a few relatively large firms), the log of each size variable was

coded.5

In addition to measuring size, I coded a dummy variable for whether a firm was a branch

office, in case the demographic composition of branch offices are influenced by a home

office outside of Silicon Valley. In particular, a woman partner may transfer from

another office of the same firm. I also control for departures at the partnership level,

although the direction of its effect is unclear. While departing partners create vacancies

that can be potentially filled by women, partner turnover may also indicate firm’s poor

health. For each year I coded the number of partners that left the firm at year’s end, then

divided each number by the total number of partners in the beginning of that year. I

similarly calculated the attrition of associates. Each attrition variable varied between 0

(no departures at that rank) and 1 (complete departure at that rank). In addition to the

proportion of departures, I also included two indicators for growth: the proportion of new

associates and the proportion of new partners. For either indicator, the rate of growth

reflects the health of the firm. As noted in Phillips (2001), law firm growth rates drive

5 As elaborated in Phillips (2002), this yields estimates that are easier to interpret than including the leverage ratio, a common measure of firm structure and performance.

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promotion rates. Thus, we would expect the growth rates to increase the likelihood of

promoting a woman to a firm’s partnership.

I also coded the proportion of women associates. Building off of Kanter (1977), Cohen,

Broschak, and Haveman (1998) note that the proportion of women at lower ranks

influences the likelihood that a woman would be promoted to higher levels of an

organization’s hierarchy. However, research by Ely (1994) on women attorneys

demonstrated that in situations where leadership is male-dominated (as is the case in this

study) junior women may view promotion to partnership as undesirable or unattainable.

Thus, it is difficult to estimate the effect of this variable. I also coded the squared term of

the proportion of women associates. However, the effect of the squared term was not

significant in any model, nor did it improve the model fit. Thus I did not include the term

in the presented results.

Silicon Valley can be roughly distinguished geographically by whether the law firm is

located in the north or south end of Silicon Valley. The north end is represented by the

cities most associated with Silicon Valley by the popular press: Palo Alto, Menlo Park,

and Redwood City. These cities host Stanford University and many of Silicon Valley’s

successful venture capitalists. Not only are these firms considered to be higher status, but

they also serve the larger and more successful corporate clients. To the extent that these

firms have greater market power, I would expect that firms located in the north end of

Silicon Valley to be less likely to promote women to the position to partner. To capture

this effect I coded a one for whether the law firm is located in any one of the three cities.

21

Firm scope was operationalized as a continuous variable from 0 to 1. It captures the

number of law practice areas that a law firm reported in the Martindale-Hubbell Law

Directory in a particular year, divided by the total number of practice areas that were

reported across all firms in that year. This measurement allowed a relative measurement

of firm scope. I also included a quadratic term for firm scope to test for curvilinear

effects. In addition to scope, dummy variables for different areas of law were coded. To

preserve statistical power, I included only those that improved the fit of the model:

corporate securities law, labor/employment law, real estate law, and intellectual property

law.

Not only may opportunities vary by practice area, but through investment in new practice

areas. To capture the role of growth through early-mover expansion, I coded a variable

one if the law firm was the first in Silicon Valley to move into a new area of law before

any other firm in the region, zero otherwise. Not only are these “local innovators”

making a substantial investment for future growth, but they are also seeking new and

different individuals to staff a new area of practice. Moreover, their innovativeness

suggests that these firms are less constrained by the set of legal norms traditionally

practiced.

To minimize concerns on unobserved heterogeneity due to characteristics of the parent

firm, I included the parent firm’s age and size. Larger and older parent firms may have

22

been more likely to have women at the associate and partner levels, confounding the

results.

Method of Estimation

I estimated the likelihood of admitting a woman to a firm’s partnership with piecewise

constant exponential models. In these models, I split the time axis into time periods

according to firm age. Although the models assumed that transition rates were constant

with each of the time periods, base rates varied freely across them. The assumption is that

period-specific baseline rates can vary across time periods, but the covariates have the

same (proportional) effects (Blossfeld and Rohwer 1995; Sørensen 1999).

The resulting models give an age-dependent constant (a “y-intercept”) for each time piece

of the model. There are different strategies for choosing the appropriate time periods.

Some theoretical predictions may require that the time periods take on particular values.

For this paper’s models, I assumed no a priori knowledge of age dependence. The null

model was an exponential model without time periods, in which it was assumed that rates

were time invariant. The y-intercepts included in the model were statistically significant

with respect to a chi-squared model improvement test.

23

RESULTS

Table 1 presents the summary statistics for each of the variables. Table 2 provides

pairwise correlations. The two key independent variables (Institutionalized Woman

Leadership and Institutionalized Woman Subordination) are correlated (r=0.36), but not

to the extent that mutlicollinearity is a concern. Two pairs of variables are correlated

over 0.50. Partner growth is highly correlated with associate growth (r=0.63). In

addition, the correlation between the proportion of years that a parent firm has women

associates (Institutionalized Woman Subordination) and the number of years a founder

formerly worked with women associates (“social contact” with women associates) is

correlated at 0.73. While not cause for alarm, it will be important to insure that the

independent variables are not misestimated when the variable for social contact with

women associates is included. All other correlations are less than 0.50.

----------------------------------------

Put Tables 1 and 2 About Here

----------------------------------------

Testing Hypothesis 1: “Proportion of Years the Parent had Women Partners”

In table 3 are the models that test my hypotheses and the alternative explanations. Model

1 estimates the firm age time pieces (y-intercepts) and the timetrend variable. As

expected, the timetrend variable is positive as a greater proportion of firms made a

woman a partner over time. Model 1 also includes the two female institutionalization

variables. Male founders were more likely to make a woman a partner in their new firms

24

when their parent firms had a history of women partners. This effect remains positive

and significant across the remainder of the models, as a host of control variables are

included and alternative explanations tested. That is, this effect is independent of the new

firm’s size, scope, market position, product/service expansion, location, growth rate,

attrition, the proportion of women attorneys, the founder’s previous position, the presence

of women when the founder first worked in the parent firm, and the size and age of the

parent firm. Additional analyses revealed that this result holds if the two

institutionalization variables are entered separately. Thus, hypothesis 1 is supported.

----------------------------------------

Put Table 3 About Here

----------------------------------------

Testing Hypothesis 2: “Proportion of Years Parent had Women Associates”

While not significant in model 1, there is evidence that hypothesis 2 is supported, albeit

conditionally. Model 2, suggests that male founders were less likely to make women

partners in their new firms when their parent firms had a history of women associates.

The fact that the effect was not significant until the control variables were included

warranted further investigation. Additional analyses revealed two control variables that,

when included, strengthened the statistical significance of the women associate

institutionalization variable: the size of the parent firm and the number of partners in the

progeny firm. Large parent firms are contexts in which the institutionalization of women

associates is more likely (the correlation between the two is 0.20, see table 2). The

25

statistical significance of H2 was also dependent upon the number of partners in the

progeny firm. The rationale here is less clear. The correlation between the number of

partners and the women associate institutionalization variable is -0.05 (not statistically

significant). It is possible that the institutionalization of women associates is more

powerful when there are fewer decision-makers in the progeny firm.

Figure 2 uses model 2 to plot the multiplier of the hazard rate of making a woman

partner. The horizontal axis represents the proportion of years that the parent firm had

women partners (bold line) and associates (dashed line), respectively. The figure

illustrates that as the proportion of years that the parent firm had women partners

increases, so does the likelihood of the progeny firm making a woman partner.

Conversely, the likelihood of the progeny firm making a woman partner decreases as the

proportion of years that the parent firm had women associates increases. Together,

model 2 and figure 2 suggest that the likelihood of a woman being made partner is

greatest when the parent firm had at least one woman partner and no women associates

over the course of its existence. The likelihood is lowest when the parent firm had a long

history of women only in the associate position.

26

Figure 2: A Progeny's Firm Likehood of Making a Woman a Partner as a Function of the Gender Hierarchy in the Parent Firm

-30

-25

-20

-15

-10

-5

0

5

10

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Proportion of Years Parent Firm Had Women Members Before Founder Left

Mul

tiplie

r of t

he H

azar

d R

ate

of M

akin

g a

Wom

an a

Par

tner

(P

roge

ny)

Women Partners in the Parent Firm Women Associates in the Parent Firm

27

Model 2 also suggests that women’s attainment is positively related to the firm’s health.

Firms experiencing high partnership growth were more likely to make a woman partner

(p<0.05). Consistent with this finding, high turnover at the partner level reduced the

chances that a woman would be made partner (p<0.05). Growth by expansion into new

markets positively influenced the likelihood of making a woman partner (p<0.10).

There was little effect for growth and turnover at the associate level. In all, the indicators

for growth were more meaningful than the size, age, and scope of the firm.

Firms located in north Silicon Valley, where the most lucrative and prestigious clients

were located, were less likely to make a woman partner (p<0.01). The practice area

indicators reveal that firms practicing labor/employment law were less likely to make a

woman partner (p<0.10). However, firms practicing in the areas of real estate and

intellectual property were more likely to make a woman partner (p<0.05).

Testing Hypotheses 3a and 3b: Differences by Founder’s Former Rank

Models 3 and 4 test whether there are differences in the hypothesized effects by the

previous rank of the founder (Hypothesis 3a and 3b). This is tested by asking whether

associates (lower-ranked members) are more likely to be influenced by the gender

hierarchy in the parent firm. If so, we should see the two institutionalized variables have

their strongest effect when carried from the parent firm by a former associate, compared

to a former partner (the reference group). Indeed, models 3 and 4 suggest that former

associates are more likely to be influenced by the parent’s gender hierarchy than former

partners. Hypothesis 3a is supported in model 3 (p<0.05). Founders who were former

28

associates are more likely to make a woman a partner when the parent firm had a history

of women leadership. The effect is substantial: a former associate is 158% times as likely

to make a woman a partner as a former partner, given the same level of institutionalized

women leadership. Hypothesis 3b is marginally supported in model 4 (p=0.08).

However, the p value represents the more conservative two-tailed test (it would be

p=0.04 using a one-tailed test), so I do consider the marginally significant result

substantively important. The evidence for H3a and H3b together suggest that a former

associate is more likely to be influenced by institutionalized women leadership and

subordination than former partners.6

For each of the five models in table 3, model fit is determined by the Bayesian

Information Criterion (BIC), which can be applied to survival models (Schwarz 1978;

Burnham and Anderson 1998; Volinsky and Raftery 1999).7 According to Raftery

(1995), BIC approximates the ratio of posterior probabilities for two competing models.

The model with the lowest BIC explains the data with the least expected loss of

information. When comparing two models the difference in the respective BIC values

allows one to determine the strength of the improvement of the better model. A

difference greater than 6 is considered as “strong” evidence that one model is better

fitting; differences greater than 10 are considered “very strong” evidence (Raftery 1995).

6 I also ran analyses that interacted former rank with the social contact control variables. None of the estimates were statistically significant. 7 The formula for BIC is G2 – df*log(N), where G2 is the likelihood-ratio Chi-square, df is the degrees of freedom, and N is the number of cases. This goodness-of-fit indicator is a more conservative means of comparing the relative fit between two models (that need not be nested), especially when the models are complex (e.g., many degrees of freedom). Compared to simply using the log-likelihood, the BIC tends to make it more difficult to reject the null when the alternative is complex.

29

For example, the improvement from model 3 to model 3 is 7.00, suggesting that the

evidence is strong that model 3 has a smaller expected loss of information.

DISCUSSION AND SUPPLEMENTAL ANALYSES

This paper presents an initial effort at understanding the relationship between

organizational genealogies and gender hierarchies. As such, I offer evidence that the

gender hierarchies of the parent firm are important to understanding the attainment of

women in that firm’s offspring. Not only do progeny respond to women leadership in the

parent firm, but to women subordination as well.

Overall, the evidence that institutionalized woman leadership enhances women’s

partnership chances in the next generation of organizations is compelling. Indeed, not

only was this hypothesized effect strong and consistent across the models of table 3, but

the direct contact variable (the Allport hypothesis for women partners) was statistically

significant as well. Men who directly interact with women in high positions, or work in

firms that have historically had women in high positions, are more likely to place women

in high-ranking positions when starting their own firms. These findings suggest that over

time, two intergenerational subpopulations of law firms may form. One subpopulation of

firms may exist in which gender inequality persist across generations. Men leave firms

without women leaders, found new firms in which women are not given leadership

positions, then spawn new firms that recreate the gender inequality. A second

30

subpopulation may consist of the intergenerational transfer of routines, cultures, or

structures that lead to new firms with woman leadership.8

Another finding of this paper is that former associates are more likely to be influenced by

the history of female leadership in the parent firm. This suggests that routines associated

with demographic composition are more likely to be transferred by lower-ranked

employees. Interestingly, Phillips (2002) found that those routines associated with

organizational structure (firm scope and span of control) were more likely to be

transferred when the founder was a former senior member of the parent firm. In fact,

Phillips (2002) argued that the higher the rank, the more resources and routines that the

founder transfers to the progeny firm. These resources and routines enhance the

progeny’s chances of survival.

These findings and arguments can be resolved by recalling Phillips’ (2002) emphasis on

the transfer of resources as well as routines. It is likely that while more resources are

transferred the higher the former rank of the founder, only those routines associated with

those resources are transferred. For example, if a former senior partner leaves a parent

firm, they are more likely to take clients (a key resource) with them. However, taking

clients will also affect the routines transferred to the progeny, especially those routines

directly associated with the client (e.g., a type of law practiced). Here resources dictate

8 I also ran models predicting the rate at which attorneys left firms to found progeny as a function of women partners and associates in the parent firm. The objective was to determine whether founders were more or less likely to have worked in firms with women partners and associates. The models revealed that firms with women partners or associates were no more likely to become parent firms (and thus sources of gender hierarchies for the next generation), although a variable for percentage of women associates was close to significance (p=.103).

31

the routines transferred. Put another way, the routines that are transferred along with key

resources are more likely to be the types of rules and procedures transferred by higher-

ranked attorneys. Founders that are lower-ranked, may be less likely to transfer

resources, but more likely to transfer taken-for-granted sets of routines (e.g., cultural

models).

Supplemental Analyses on Gender Hierarchies as Organizational Routines

I argue that gender hierarchies are transferred along with the same routines that reproduce

the progeny’s structure and organization of work. The imagery is one of founders taking

a bundle of routines with them upon the founding of the progeny. If true, the transfer of

gender hierarchies should be stronger for those progeny that also reproduce other aspects

of the parent’s organization of work. Drawing from Phillips’ (2002) observation that

progeny often had similar leverage ratios (the span of control is calculated as the ratio of

associates to partners and captures the organization of work) as their parent firms, I coded

the absolute value of the difference between the parent’s leverage ratio and the progeny’s.

The greater the difference in leverage ratios, the fewer routines transferred from the

parent to the progeny. To the extent that gender hierarchy is transferred as an

organizational routine, those progeny that are different from their parent firms (with

respect to the leverage ratio) should be less likely to replicate of the parent’s gender

hierarchy. Interacting an “intergenerational difference of leverage ratios” variable with

Institutionalized Female Leadership should result in a negative and significant variable.

Interacting this variable with Institutionalized Female Subordination should produce a

positive and significant variable.

32

Table 4 presents the estimation of the models that examine the relationship between the

proposed institutionalized effects and structural similarity. Model 1 shows that there is

no main effect for the difference in parent and progeny leverage ratios. The coefficient is

negative but the z-statistic is only -0.25. Model 2 includes the covariate for the

interaction between the difference in leverage ratios and Institutionalized Female

Leadership. In support of my thesis, the coefficient is negative and statistically

significant (p<0.05). The finding suggests that routines associated with Institutionalized

Female Leadership are less likely to be transferred when other routines are not

transferred. Put another way, routines that replicate the parent firm’s organization of

work either include or are transferred along side routines that replicate female leadership.

Model 3 represents the interaction between the difference in leverage ratios and the

Institutionalized Female Subordination variable. The coefficient is again in the expected

direction (positive). However, the effect is not statistically significant. Thus, it appears

that the institutionalization of women’s subordination is independent of the replication of

other routines that reflect the organization of work. Overall, Table 4 lends credence to

the argument that gender hierarchies are embedded in the routines and rules that founders

take into their new firms.

----------------------------------------

Put Table 4 About Here

----------------------------------------

33

Other Supplemental Analyses While restricting the sample to progeny that were founded by men was important to

provide the cleanest test of my hypotheses, another critical question involves

understanding the dynamics of women founded firms. While beyond the scope of this

paper, I did rerun the analysis for all progeny since 1970, including a dummy variable for

whether the firm had any women founders. I found that women founded firms were more

likely to partner an addition woman (p<0.001). In addition, I found that Hypotheses 1

and 2 were supported in this model. That is, the institutionalized woman leadership and

subordination effects occur independent of the gender of the founders. The findings

involving the former rank of the founder (H3a and H3b) are contingent upon the founders

being male. Future research should further explore differences by the founder’s gender.

I also reran each of the analyses with different weights for the institutionalization and

social contact variables. Whereas the institutionalization variables were coded as a one if

a woman was an associate or partner for the entire life of the firm, I multiplied the

original variables by the proportion of women at that particular level. For example, if

women partners were an average of 10% of the parent firm’s partners over its life cycle,

the weighted variable would equal 0.10. The weighted variables did not alter the

significance of any of the results however. The only exception is the social contact

control variable for women associates. In these models, the weighted operationalization

of the variable was stronger (negative and statistically significant) than the results

reported in table 3.

34

Conclusion

In sum, my findings add weight to the role of organizations in stratification and gender

inequality by providing evidence that opportunity structures are reproduced across

organizational generations. Within the literature on law firms, there is growing attention

to the persistence of gender inequality (Mossman 1988; Abel 1989). I argue that we

should more often direct our attention to the intergenerational transfer of institutionalized

structures, routines, and values that reproduce gender inequalities. Understanding the

diversity of opportunity structures may not be possible without understanding the

opportunity structures of the previous organizational generation and the characteristics of

organizations that spawn organizational offspring.

While promising, the empirical support of my arguments must come with an

understanding of the context. The organizational structure of law firms and the market

for legal services places a unique set of demands on all attorneys, independent of gender.

Associates are known to labor intensively for several years with little chance of making

partner. Moreover, law firms are human capital-intensive organizations. They are

similar to other professional service organizations where the transfer of routines from a

parent to its offspring may be the easiest to measure. Future research should seek to

verify whether my findings apply to other organizational forms.

My data typically involve small and young organizations. The average sizes of the parent

and progeny firms were 9.8 and 4.6, respectively. The average age of a parent firm was

11.96. For progeny the average age was 6.57. While this may prompt concerns about

35

external validity, there is a substantial benefit. The use of small firms increases the

relevance of group-level research on the emergence and persistence of gender hierarchies

(Berger, Rosenholtz, and Zelditch 1980; Ridgeway 1997; Lucas 2003; Troyer 2004) since

they are closest to the laboratory groups in which “micro-institutionalization” has been

experimentally identified. Moreover, the size and age of my firms allows comparison to

other studies on entrepreneurship, especially those that also examine the attainment of

women (Baron, Hannan, Hsu, and Kocak, 2002, Stuart and Ding 2004)

In addition to exploring other types and sizes of organizations, future work should more

intently document the transfer of routines from the parent to the progeny. Specifically,

what precisely is transferred from the parent to the progeny that causes the persistence of

gender hierarchies? While the findings in table 4 are shed some light on this question,

these data do not allow me to definitively distinguish the transfer of routines as policies

(e.g., recruitment and promotion policies) or as culture (Schein 1992). Future

development should seek to understand whether the transfer need be purposive, and

whether its implications for gender hierarchies intentional.

36

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43

Table 1. Summary Statistics for Silicon Law Firm Progeny Firms, 1970-1996. N = 623 Firm-Years (99 Firms).

Variable Mean S.D. Min Max DV: Firm has a woman partner 0.03 0.16 0 1 Firm age 6.57 5.66 1 26 Log(Time trend) 2.59 0.64 0 3.26 Prop yrs parent had women partners 0.08 0.26 0 1 Prop yrs parent had women assoc. 0.10 0.23 0 1 Yrs worked w/ women partners 0.35 1.44 0 13 Yrs worked w/ women associates 0.82 2.19 0 13 Log(partners) 1.03 0.55 0 3.04 Log(associates) 0.59 0.66 0 2.77 Firm is a branch office 0.16 0.37 0 1 Relative scope 0.11 0.06 0.01 0.34 New Market Expansion 0.14 0.35 0 1 Firm located in North SV 0.44 0.50 0 1 Associate growth rate 0.05 0.20 0 1 Associate attrition rate 0.10 0.25 0 1 Partner growth rate 0.06 0.15 0 1 Partner attrition rate 0.04 0.16 0 1 Securities law 0.22 0.42 0 1 Real estate law 0.40 0.49 0 1 Labor/Employment law 0.29 0.45 0 1 Intellectual property law 0.11 0.31 0 1 Prop of women associates 0.10 0.24 0 1 Parent firm age when founder left 11.96 11.41 1 60 Parent firm size when founder left 8.04 11.43 1 96 Prop women partners when founder joined parent 0.01 0.07 0 0.41 Prop women assoc when founder joined parent 0.03 0.15 0 1 Founder was a former associate 0.35 0.48 0 1

44

45

Table 2. Pairwise Corrleations for Silicon Valley Law Firm Progeny Firms, 1970-1996 N=623 Firm Years (99 Firms) Firm makes a

wmn partner Firm age Log (partners) Log (assoc.) Rel. Scope New Market

Expansion Located in North SV

Branch Office Log (Time trend)

Partner attr. rate Assoc. attr. rate Prop wmn assoc.

Firm makes a wmn partner

1

Firm age 0.0608 1

Log (partners) 0.1077* 0.2499* 1

Log (assoc.) 0.0658 0.2168* 0.0255 1

Rel. Scope 0.0445 -0.0409 0.2854* 0.0694 1

New Market Expansion -0.0061 0.2280* 0.1872* 0.0192 0.3765* 1

Located in North SV -0.1030* -0.0567 0.0816* -0.0157 0.2313* 0.0673 1

Branch Office 0.1515* 0.0441 0.2657* 0.4387* 0.1529* -0.0976* -0.1021* 1

Log (Time trend) 0.0952* 0.0579 -0.1234* 0.0046 -0.4175* -0.1900* -0.0051 -0.0542 1

Partner attr. rate 0.0143 0.0273 0.2418* -0.0237 0.0794* -0.0512 -0.0653 0.1616* 0.0185 1

Assoc. attr. rate -0.0145 0.0324 -0.1188* 0.3425* -0.0096 -0.0272 -0.0239 0.1306* 0.0319 0.0825* 1

Prop wmn assoc. 0.0478 0.1440* 0.1402* 0.1002* 0.024 0.0933* 0.0799* 0.0386 0.1066* 0.0966* 0.0326 1

Partner growth rate 0.1385* -0.053 0.3186* 0.0194 0.1140* -0.065 0.0108 0.0988* 0.0342 0.1987* 0.0071 0.1456*

Assoc. growth rate 0.029 -0.0134 0.1315* 0.2021* 0.0912* -0.0065 0.0478 0.075 0.0093 0.0004 0.1185* 0.0288

Real estate law 0.0534 -0.1740* 0.1354* -0.1111* 0.3645* -0.0143 0.1982* 0.0293 -0.0929* -0.0488 -0.0037 0.0372

IP law 0.072 -0.0914* 0.0831* 0.0762 0.1970* 0.1257* 0.1613* 0.0145 0.2270* -0.0069 -0.0356 -0.0402

Securities law 0.0111 -0.0828* 0.2406* 0.067 0.4958* 0.1339* 0.2983* 0.0536 0.0204 0.0314 0.0345 0.1310*

Labor/Empl. Law 0.0321 -0.0865* 0.1187* 0.0461 0.2580* 0.1589* -0.045 0.0847* 0.1269* 0.0889* 0.0316 0.0127

Prop yrs parent had women partn.

0.1119* -0.0993* 0.0471 0.2296* 0.1960* -0.1215* 0.1413* 0.3418* 0.1650* 0.1163* 0.0481 0.0185

Prop yrs parent had women asso.

0.0139 -0.1503* -0.047 0.0910* -0.0701 -0.068 -0.1184* 0.1313* 0.2830* 0.0135 -0.0356 -0.0403

Yrs worked w/ women partners

0.045 -0.1277* -0.1022* -0.0459 -0.1059* -0.0713 -0.1500* 0.1016* 0.1794* -0.0379 0.0063 -0.0183

Yrs worked w/ wmn associates

-0.0419 -0.1291* -0.1776* 0.0114 -0.1341* -0.03 -0.1171* 0.0386 0.2487* -0.0675 -0.0421 0.005

Parent firm age -0.0002 0.1040* 0.025 -0.1890* -0.0286 -0.0278 -0.1060* -0.1696* 0.0858* 0.0722 -0.0739 -0.0302

Parent firm size 0.0811* -0.1041* -0.1074* 0.0031 -0.1422* -0.0891* -0.0345 -0.1027* 0.1819* -0.0916* 0.01 -0.0184

Prop wmn partne when founder joined parent

0.0309 0.0460 0.2658* -0.0372 0.1088* -0.0796* -0.0775 0.0381 0.1039* 0.2592* -0.0331 -0.0523

Prop wmn assoc when founder joined parent

0.0413 -0.0701 -0.0836* -0.0294 -0.1025* -0.0596 -0.1381* 0.0117 0.0991* 0.1542* -0.0255 -0.0211

Founder: former assoc. 0.0292 0.1758* 0.3448* 0.0542 0.1524* 0.2999* 0.0114 0.0202 -0.0287 0.0701 -0.012 0.0145

46

Table 2 (cont') Partner

growth rate

Parent Assoc. growth rate

Real estate law

IP law Securities law

Labor/Empl. Law

Prop yrs parent had women partn.

Prop yrs parent had women assoc.

Yrs worked w/ women partners

Yrs worked w/ women associates

Parent firm age

firmsize

Partner growth rate 1

Assoc. growth rate 0.6317* 1

Real estate law 0.021 -0.0221 1

IP law 0.0217 0.0376 -0.0072 1

Securities law 0.1182* 0.1390* 0.3046* 0.3167* 1

Labor/Empl. Law 0.1062* 0.0494 -0.1916* 0.1504* 0.2188* 1

Prop yrs parent had women partn.

0.1103* 0.1276* 0.063 0.0875* 0.2015* 0.2204* 1

Prop yrs parent had women asso.

-0.0026 0.0245 0.002 0.1489* 0.0263 0.2026* 0.3569* 1

Yrs worked w/ women partners

-0.0595 -0.034 -0.0692 0.0137 -0.0758 0.0338 0.0487 0.3853* 1

Yrs worked w/ wmn associates

-0.0552 -0.0096 -0.0715 0.074 -0.0855* 0.1829* 0.1271* 0.7329* 0.3239* 1

Parent firm age 0.0426 -0.0582 -0.0766 -0.0296 -0.1857* 0.2552* -0.0717 0.051 0.1278* 0.1873* 1

Parent firm size -0.0853* -0.031 0.015 0.1003* -0.0643 0.1171* -0.0322 0.2124* 0.1201* 0.2536* 0.4182* 1

Prop wmn partne when founder joined parent

0.0553 0.0457 -0.0771 -0.0256 0.0120 0.3144* 0.1303* 0.0859* -0.0483 0.0155 0.4218* -0.0878* 1

Prop wmn assoc when founder joined parent

-0.0853* -0.0310 0.0028 0.0063 0.0093 -0.0340 0.0755 0.1259* -0.0088 0.0147 -0.1300* -0.0245 -0.0360 1

Founder: former assoc. 0.0084 -0.0026 -0.0403 0.1258* 0.1578* 0.2413* -0.1335* 0.022 0.0172 -0.0515 0.4236* 0.1674* -0.0311 0.3092* 1

Table 3. MLE of a Firm Having a Woman Partner (Testing H1-H3). Silicon Valley Law Firms (1970-1996). N = 623 firm-years; 99 firms. * = p < 0.05 Variable (1) (2) (3) (4) Hypo Firm age: 0 to 3 years

-9.78 (2.62)

-1.46 (12.46)

-21.58 (14.22)

-0.32 (13.67)

Firm age: 3 to 10 years

-9.68 (2.62)

0.25 (12.40)

-18.26 (13.75)

3.81 (13.24)

Firm age: 10+ years

-8.84 (2.61)

5.54 (12.97)

-11.72 (13.01)

10.03 (13.76)

Time trend (logged) Prop. yrs parent had women partners

2.01* (0.90) 1.56*

6.84* (3.16) 20.76*

9.68* (4.13) 18.82*

7.69+ (4.38) 26.88*

(0.67) (7.58) (6.79) (9.73) H1 Prop. yrs parent had women associates

-1.20 (1.10)

-13.57* (5.89)

-20.54+ (11.36)

-15.61 (13.99) H2

Yrs worked w/ women partners

2.07* (0.76)

2.03* (0.86)

3.29* (1.52)

Yrs worked w/ women associates

-0.42 (0.48)

-0.59 (0.57)

-1.37 (2.81)

Log(partners)

0.41 (1.23)

0.41 (1.29)

0.01 (1.77)

Log(associates)

-0.19 (0.87)

-2.11 (3.78)

-0.75 (1.28)

Firm is a branch office

1.45 (2.03)

2.36 (2.40)

1.48 (2.98)

Relative scope

-23.11 (22.12)

-40.51+ (23.36)

-42.15 (33.40)

New Market Expansion

9.28+ (5.03)

9.56* (4.13)

10.84+ (6.13)

Firm located in North Silicon Valley

-13.03* (4.07)

-15.22* (5.49)

-15.80* (6.17)

Partner growth rate

13.52* (5.72)

15.98* (6.73)

16.65* (7.82)

Partner attrition rate

-15.34* (7.65)

-17.82* (8.90)

-18.15+ (9.33)

Associate growth rate

-5.02 (3.05)

-5.65+ (3.15)

-6.35 (4.43)

Associate attrition rate

-2.53 (2.69)

-2.11 (3.78)

-3.83 (4.26)

Prop of women associates

-1.72 (2.36)

-0.97 (2.71)

-1.43 (2.74)

Securities law

-0.94 (2.25)

-1.82 (2.73)

-1.67 (2.81)

Real estate law

6.33* (2.08)

7.68* (2.60)

8.58* (3.05)

Labor law

-6.08+ (3.30)

-4.34* (2.04)

-7.08+ (3.97)

Intellectual property law

6.12* (2.32)

8.93* (3.64)

7.55+ (3.97)

Parent firm age when founder left

-0.18 (0.17)

0.04 (0.15)

-0.30 (0.22)

Parent firm size when founder left

0.11 (0.07)

0.03 (0.06)

0.14+ (0.09)

Prop wmn partners when founder joined parent

28.34 (23.67)

12.10 (15.62)

39.61 (30.72)

Prop wmn assoc when founder joined parent -7.10 (5.88)

-9.98 (8.55)

10.64 (8.11)

Founder was a former associate (Former assoc.)*( Prop yrs parent had women partners)

0.30 (1.90)

-1.88 (2.28) 10.92*

2.07 (2.32)

(4.83) H3a

(Former assoc.)*( Prop yrs parent had women assoc)

-22.26+ (12.83) H3b

N 623 622 622 622 BIC model fit -103.02 -177.22 -184.22 -183.50 BIC improvement versus previous model 4.68 74.21 7.00 0.73 Wald Chi-square 174.04*

(6) 32.36 (28)

26.08* (30)

24.48 (30)

47

Table 4. MLE of a Firm Having a Woman Partner (Testing Structural Similarity). Silicon Valley Law Firms (1970-1996). N = 623 firm-years; 99 firms. * = p < 0.05 Variable (1) (2) (3) Firm age: 0 to 3 years

-0.62 (13.09)

-19.19 (15.52)

-0.23 (13.41)

Firm age: 3 to 10 years

1.20 (13.13)

-15.10 (15.15)

1.85 (13.42)

Firm age: 10+ years

6.51 (13.75)

-8.51 (14.49)

6.74 (14.02)

Time trend (logged) Prop. yrs parent had women partners

6.68* (3.15) 21.06*

9.75* (4.27) 22.72*

6.78* (3.36) 21.10*

(7.77) (7.56) (7.77) Prop. yrs parent had women associates

-13.51* (5.91)

-22.43+ (12.09)

-14.15* (6.66)

Yrs worked w/ women partners

2.12* (0.81)

2.30* (0.93)

2.34* (0.94)

Yrs worked w/ women associates

-0.47 (0.54)

-0.51 (0.60)

-0.61 (0.74)

Log(partners)

0.27 (1.36)

0.28 (1.62)

0.32 (1.45)

Log(associates)

-0.04 (1.04)

0.38 (1.13)

-0.20 (1.16)

Firm is a branch office

1.38 (2.06)

1.57 (2.14)

1.23 (2.27)

Relative scope

-24.64 (23.51)

-29.67 (26.28)

-26.23 (23.95)

New Market Expansion

9.57+ (5.23)

9.32* (4.69)

9.55+ (5.28)

Firm located in North Silicon Valley

-13.09* (4.11)

-18.47* (6.32)

-12.87* (4.15)

Partner growth rate

13.79* (5.91)

17.92* (7.38)

12.80* (6.16)

Partner attrition rate

-15.58* (7.82)

-19.65* (9.28)

-14.54+ (8.08)

Associate growth rate

-5.33 (3.32)

-7.47+ (4.04)

-4.73 (3.47)

Associate attrition rate

-2.55 (2.72)

-4.38 (3.43)

-2.98 (3.11)

Prop of women associates

-1.72 (2.37)

-0.82 (2.61)

-1.37 (2.57)

Securities law

-0.86 (2.30)

2.08 (2.86)

-1.06 (2.47)

Real estate law

6.45* (2.19)

7.43* (2.60)

6.42* (2.17)

Labor law

-6.02+ (3.28)

-4.86* (2.46)

-6.08+ (3.33)

Intellectual property law

6.18* (2.37)

9.88* (3.79)

5.82* (2.55)

Parent firm age when founder left

-0.18 (0.17)

-0.05 (0.16)

-0.20 (0.18)

Parent firm size when founder left

0.11 (0.07)

0.07 (0.07)

0.12 (0.07)

Prop women partners when founder joined parent 29.07 (23.82)

16.74 (21.46)

30.64 (24.35)

Prop women associate when founder joined parent -6.85 (5.89)

-2.70 (8.47)

-7.83 (6.33)

Founder was a former associate

0.02 (2.25)

-1.12 (2.63)

0.29 (2.33)

Logged Absolute Difference in Ratio (Ratio diff)*( Prop yrs parent had women partners)

-0.17 (0.70)

-0.14 (1.09) -3.07*

-0.17 (0.74)

(1.51)

(Ratio diff)*( Prop yrs parent had women assoc) 2.98 (4.96)

N 622 622 622 BIC model fit -177.27 -182.26 -177.88 BIC improvement versus previous model 4.99 0.61 Wald Chi-square

32.36 (30)

26.24* (31)

31.40 (31)

48

49