Private Equity & Investment Funds

Antitrust follows capital. A sponsor that buys a platform and adds to it, a growth fund that takes a large minority stake, a fund whose portfolio company is being squeezed by a dominant supplier, a litigation funder deciding whether an antitrust claim is worth financing — each is making an antitrust decision, whether or not anyone calls it one. Bona Law is an antitrust boutique. We handle the competition issues for private equity sponsors, their portfolio companies, venture and growth investors, litigation funders, and fund-owned businesses: on the deal side, through the holding period, and on the claims side, where antitrust stops being a risk to manage and becomes an asset to value.

Our merger team has run the process from every seat — in-house at a global manufacturer filing hundreds of Hart-Scott-Rodino notifications, inside the European Commission’s Merger Task Force, at the Department of Justice and a state attorney general’s office challenging deals, and across the table from the FTC and DOJ in merger reviews and second requests. Our litigators bring and defend the cases that acquisition strategies produce: monopolization claims against acquisition-built dominant firms, the class actions that follow consolidation, and the disputes that arise when a fund-owned company has been harmed. And because Bona Law has no corporate transactions practice, the deal firms that serve sponsors bring us in without hesitation. We solve the antitrust problem and hand the client back.

Why private equity sponsors and investment funds hire Bona Law

We are antitrust counsel, not deal counsel. Excellent corporate and private equity firms run the transaction. We integrate into their deal teams to handle reportability, filings, merger-control strategy, and agency negotiation — without overlap or turf friction. Corporate law firms without antitrust practice groups regularly retain us for their sponsor clients’ filings, and sponsors rely on us across their portfolios, from fund-structure reportability analysis to add-on acquisitions. Learn how we work alongside other firms on our Antitrust Co-Counsel page.

We know how the agencies think because we have been them. Steve Cernak spent more than twenty years as in-house antitrust counsel at General Motors, leading its merger reviews and filing hundreds of HSR notifications. Luis Blanquez served on the European Commission’s Merger Task Force. Paul Moore investigated more than one hundred proposed transactions at the DOJ Antitrust Division and, as a California enforcer, was lead attorney for the state in two litigated merger challenges. Kristen Harris represents companies before the DOJ, FTC, and foreign authorities in merger reviews and first saw the process from inside the FTC’s Bureau of Competition. When your filing lands on a reviewer’s desk, we know what the reviewer is looking for.

We track the rules as they change — and they are changing fast. In 2026 alone, a federal court vacated the expanded HSR form, the FTC collected a then-record $12 million penalty under Rule 801.90 from parties who structured an acquisition to stay under the filing threshold, and the DOJ announced a record $250 million HSR penalty against a private equity sponsor for filing failures across at least sixteen transactions. Our attorneys’ HSR analysis on The Antitrust Attorney Blog is read by practitioners and enforcers worldwide, and the same attorneys prepare our clients’ filings.

We work the deal side and the claims side. We counsel acquirers on the antitrust exposure that serial acquisitions create, and we litigate monopolization claims against acquisition-built dominant firms. We defend companies in the class actions that follow consolidation, and we represent fund-owned businesses harmed by dominant suppliers and platforms. Seeing both chairs is how we spot the weakness in an acquisition program before a plaintiff does — and the value in a portfolio company’s claim before a defendant expects it. On the claims side we are independent of the platform giants, which matters when the counterparty is one of them.

Boutique economics, senior attention. Reportability answers come quickly and are often available on a fixed fee. Routine filings are quoted, predictable projects. When a deal or a claim has substance to it, you work directly with partners who have done this hundreds of times — with none of the leverage-model overhead. For the right claim we consider contingency and hybrid arrangements, and we have experience working with litigation funders.

Representative experience

The matters below are Bona Law engagements. Most sponsor, fund, and merger-clearance clients are confidential, so descriptions are generalized.

U.S. and cross-border merger clearance across multiple transactions for private equity sponsors and their portfolio companies — including parallel HSR filings and coordinated competition filings before the European Commission, the UK Competition and Markets Authority, and other non-U.S. authorities, with second-request response experience.
HSR reportability analysis and filings for sponsor platform and add-on acquisitions — fund and ultimate-parent-entity analysis, aggregation across funds and portfolio companies, and the treatment of management rollovers and side investments — for sponsors directly and for the corporate law firms that represent them.
Antitrust counseling on strategic acquisitions across multiple industries, for acquirers ranging from startups to Fortune 100 companies: pre-deal risk assessment, HSR notification strategy, market definition, and remedy negotiation.
Advised multiple litigation finance companies on the strength and risks of potential antitrust claims — liability theories, market definition and damages, evidentiary considerations, and the litigation-risk factors relevant to funding decisions.
Independent evaluations of potential antitrust claims for investment funds and fund-owned companies weighing claims against dominant suppliers and platforms.
Lucasys, Inc. v. PowerPlan, Inc. — Section 2 monopolization case on behalf of a software entrant against a Roper Technologies subsidiary that controlled roughly 99% of the utility-management software market. After more than four years of litigation, including defeat of the motion to dismiss, the case resolved with a $24 million settlement and injunctive relief protecting our client’s customer relationships.
Post-acquisition counseling for a cryptocurrency infrastructure operator that acquired a controlling stake in a software vendor whose customers included the operator’s competitor — the Section 2 refusal-to-deal and vertical-foreclosure exposure that constrains how a newly affiliated input supplier may treat that rival.
The class-action exposure a portfolio inherits: we defeated indirect-purchaser class certification for a Japanese capacitor manufacturer in In re Capacitors Antitrust Litigation; won summary judgment for Foster Farms in the nationwide turkey price-fixing MDL; and defended a national trucking company in a no-poach class action. See our Antitrust Class Actions practice.
Defended a company in a DOJ Antitrust Division grand-jury investigation of alleged price fixing, persuading the Division not to seek an indictment after the document production. See Antitrust Investigations.
Merger-review advocacy: amicus brief for a bipartisan group of 34 Members of Congress on the FTC’s authority and the governing standard in the Illumina-Grail merger review, and an amicus brief for leading antitrust law professors in the Second Circuit appeal over the Disney-led sports-streaming joint venture.
Outside trial counsel to the California Attorney General in People v. Vitol, a Cartwright Act enforcement action against global gasoline trading firms resolved for $50 million — state-enforcement experience that informs our work under California’s new premerger and healthcare-transaction laws.

Our private equity and investment funds team

Steve Cernak (Partner, Detroit) leads the firm’s merger and compliance work. He spent more than twenty years as in-house antitrust counsel at General Motors, ultimately responsible for the company’s global antitrust compliance, merger reviews, and litigation — filing hundreds of HSR notifications and negotiating joint ventures among rivals. He is a former Chair of the ABA Antitrust Law Section, has been recognized by Best Lawyers in antitrust every year since 2020, and is the author of the blog’s long-running HSR series, including its early warnings on private equity fund structures and interlocking directorates.

Luis Blanquez (Partner, San Diego) served with the European Commission’s Merger Task Force, where his reviews included Oracle/PeopleSoft, and then spent a decade at major international firms in Brussels, Madrid, and London on merger control and cartel matters. He coordinates our clients’ EU, UK, and other non-U.S. filings, is Vice Chair of the ABA Antitrust Law Section’s Media and Technology Committee and former Vice Chair of its Distribution and Franchising Committee, and co-authors the blog’s Section 8 and HSR analysis.

Kristen Harris (Of Counsel, San Diego) represents companies and individuals before the DOJ, FTC, and foreign competition authorities in merger reviews and investigations, served as outside counsel to the California Attorney General’s Office in People v. Vitol, and clerked with the FTC’s Bureau of Competition during law school. She is Vice Chair of the ABA Antitrust Law Section’s Trade, Sports, and Professional Associations Committee, formerly served as Counsel to the Section’s Chair, and co-authored the blog’s analysis of the Rule 801.90 penalty.

Paul Moore (Partner, San Diego) served in the DOJ Antitrust Division and as a senior Deputy Attorney General in the California Attorney General’s Office, where he investigated corporate conduct and proposed transactions and litigated merger challenges on behalf of the State — including as lead attorney for California in the joint federal-state challenge that stopped the proposed DraftKings/FanDuel merger and in the successful challenge to the Valero/Plains All American acquisition. He wrote the blog’s guide to merger reviews before the federal agencies and the California AG.

Jarod Bona (CEO and Partner, San Diego) founded Bona Law in 2014 after a dozen years practicing antitrust at DLA Piper and Gibson Dunn. He also founded The Antitrust Attorney Blog, one of the most-read antitrust websites in the world. Bona Law is recognized in the Chambers Spotlight guides for antitrust in both New York and California.

Jon Cieslak (Partner, San Diego) led the firm’s monopolization case for Lucasys against PowerPlan — the $24 million recovery against an acquisition-built dominant firm — and represents Zulily in its antitrust case against Amazon. He has defended price-fixing class and MDL claims in the electronics, media, and other industries, persuaded the DOJ to close no-poach investigations without charges, and litigated securities-fraud, trade-secret, and unfair-competition disputes during nearly a decade at Cooley before joining Bona Law.

Aaron Gott (Partner and Chief Operating Officer, Minneapolis) has served as lead counsel for defendants in several of the country’s largest price-fixing MDLs — including In re Turkey, In re Disposable Contact Lens, and In re Capacitors — and argues appeals across the federal circuits. His analysis of acquisition-monopoly risk in the fire-apparatus MDL explains what serial acquisitions mean for sponsors and the companies they build.

Bona Law has more than 15 antitrust attorneys across San Diego, New York, Dallas, Detroit, and Minneapolis.

How we help

HSR reportability desk — fast, fixed-fee reportability answers for sponsors and their deal counsel; fund and ultimate-parent-entity analysis; aggregation and rollover questions; Rule 801.90 structuring review. See Mergers & Acquisitions.
Filings and merger clearance — HSR notifications, waiting-period management, second-request strategy and response, remedies, and coordinated EU, UK, and other non-U.S. filings.
Add-on program screen — a market-by-market antitrust assessment of a platform’s acquisition pipeline before the next deal, with document and deal-model discipline built in.
Section 8 board-seat audit — portfolio-wide review of director and observer appointments against the 2026 thresholds and the agencies’ current enforcement theories, with remediation.
State filing readiness — Washington, Colorado, and California premerger requirements; healthcare-transaction review under AB 1415 and SB 351 and comparable state laws. See State Attorney General Antitrust.
Portfolio compliance and information-exchange protocols — sponsor-level programs for portfolio companies in overlapping markets; pricing, distribution, labor, trade-association, and algorithmic-pricing counseling. See Antitrust Counseling and Compliance.
Post-acquisition integration counseling — Section 2 and vertical-foreclosure analysis when an acquired business supplies or serves a competitor.
Investigations and class-action defense — CIDs, second requests, grand-jury subpoenas, and price-fixing, no-poach, and consolidation class actions for portfolio companies. See Antitrust Investigations and Antitrust Class Actions.
Independent claim evaluation — a fixed-fee assessment of whether a fund’s or a portfolio company’s antitrust claim is worth pursuing.
Opt-out and direct-action analysis — class-versus-direct-action economics for portfolio companies holding purchaser claims. See our opt-out explainer.
Plaintiff litigation for fund-owned companies — monopolization, exclusionary-conduct, and cartel claims on hourly, contingency, or hybrid terms. See Antitrust Litigation and Monopolization.
Claim assessments for litigation funders — liability, damages, and risk analysis in investment-committee form.
Co-counsel for deal firms and litigation firms — we handle the antitrust problem inside your team and hand the client back. See Antitrust Co-Counsel.

Where antitrust meets the fund: the deal

HSR for funds, add-ons, and platforms

Private equity deals raise HSR questions that ordinary corporate transactions do not: which fund is the ultimate parent entity, how holdings aggregate across funds and their associates, when management rollovers and side investments count toward the size of the transaction, whether a foreign fund’s U.S. nexus triggers a filing, and how to document a structure that has a real business rationale so it is never mistaken for an avoidance device under Rule 801.90. We answer these questions for sponsors and their deal counsel deal after deal. The Mergers & Acquisitions page describes the HSR process, current thresholds and fees, and what triggers a second request; our library explains what an HSR filing requires and the blog covers the aggregation traps, the ten minefields, how to avoid a second request, and what happens when an agency calls.

Roll-up risk: the acquisition-monopoly theory

Add-on programs are the engine of buy-and-build, and most add-ons are individually too small to report. That is precisely why enforcers and plaintiffs now look at them in the aggregate. The FTC’s case against U.S. Anesthesia Partners and its sponsor — settled with the sponsor in 2025 and with the operating company in April 2026 — rested on the theory that a series of acquisitions, none independently unlawful, built a dominant position that raised prices. The fire-apparatus MDL now consolidating in Wisconsin applies the same theory in a private class action against a private-equity-built duopoly, with cities as plaintiffs. Section 7 of the Clayton Act reaches acquisitions whose effect “may be” to lessen competition substantially; Section 2 of the Sherman Act reaches a pattern of acquisitions undertaken to acquire or maintain monopoly power; and the 2024 federal inquiry into serial acquisitions made clear that sub-threshold deals are not below the agencies’ line of sight. We help sponsors screen a platform’s markets before the next add-on, discipline the deal documents that later become exhibits, and — when a program is challenged — defend the companies that built it. See Monopolization and Exclusionary Conduct.

Board seats and Section 8

Section 8 of the Clayton Act bars a person from serving as an officer or director of two competing corporations above the annually adjusted thresholds — $54,402,000 in capital, surplus, and undivided profits for 2026, with a de minimis exception where either company’s competitive sales fall below $5,440,200. The agencies take the position that the prohibition reaches a sponsor that appoints different people to competing portfolio boards, have secured director resignations to unwind an interlock between two private-equity-owned providers, and have signaled that LLCs and board observers are not safe harbors. A one-year grace period applies when companies become competitors after the appointment. We audit board appointments across a portfolio, structure observer and information rights, and resolve interlocks before an agency does. Our partners have written about the issue since 2017 and updated the analysis for private equity clients.

State review: the second filing regime

Washington and Colorado premerger notification laws took effect in 2025, and California’s Uniform Antitrust Premerger Notification Act arrives January 1, 2027 — each with nexus tests that reach transactions with in-state sales far below the federal threshold. Separately, California’s AB 1415 and SB 351, effective January 1, 2026, extend healthcare-transaction review to private equity groups and management services organizations, joining Oregon, Massachusetts, and other states that scrutinize physician-practice and MSO deals. Our State Attorney General Antitrust practice includes former state and federal enforcers, and we served as outside trial counsel to the California Attorney General; we know how a state reviewer reads a sponsor’s add-on. See also our Healthcare industry page.

Global filings

For portfolios with European or other non-U.S. operations, we coordinate parallel filings before the European Commission, the UK CMA, and other authorities — with direct ex-Commission experience — and we explain when two foreign companies must file in the United States and what a European filing requires. See our International Clients page.

Venture and growth investments

Late-stage financing rounds, secondary purchases, and the acqui-hire and licensing structures Big Tech has used to enter the AI market without a filing all raise reportability questions that deal teams tend to ask late. We give venture and growth investors quick, quoted answers, and we counsel their portfolio companies on the competition issues that come with scale — see our antitrust resources for start-ups.

Where antitrust meets the fund: the holding period

A sponsor’s antitrust exposure does not end at closing. Portfolio companies in adjacent or overlapping markets share an owner, sometimes share directors, and often share data — the ingredients of an information-exchange or hub-and-spoke allegation if the sharing is not structured. Pricing and distribution programs that were fine for one company become a pattern across five. Labor practices spread across a portfolio; so do trade-association memberships and algorithmic pricing tools. And a newly acquired input supplier that serves a rival inherits Section 2 obligations the deal model never priced. We build sponsor-level compliance programs and information-exchange protocols; counsel portfolio companies on pricing, MAP, and distribution, labor-market and non-compete issues, and platform conduct; and provide post-acquisition integration counseling where the new business touches a competitor. When a portfolio company receives a civil investigative demand, a grand-jury subpoena, or a class complaint, our investigations and class-action defense teams have handled the largest matters of their kind.

Where antitrust meets the fund: the claims

Antitrust claims are portfolio assets, and most portfolios hold more of them than their owners realize. A portfolio company that bought inputs from a cartel is a class member with an opt-out deadline and, sometimes, a direct action worth far more than its class share. A company squeezed by a dominant supplier, platform, or standard-setting body may have a Section 2 claim with treble damages and fee-shifting. A company competing against an acquisition-built monopolist may have the case that changes its market. And after a government enforcement win, Section 5(a) of the Clayton Act and the Google decisions give private plaintiffs a running start. The question a fund actually needs answered is whether a particular claim is worth pursuing — a question that depends on liability theory, market definition, antitrust injury, damages, evidence, the defendant’s durability, and the fund’s exit horizon.

We answer that question for a living. We evaluate claims independently for funds and fund-owned companies, often for a fixed fee, with no expectation that we will bring the case — and we will say so when the claim is not worth the money. We advise portfolio companies on whether to opt out of purchaser class actions and, when the answer is yes, bring the direct action. We represent fund-owned companies as plaintiffs — the case we brought for Zulily against Amazon and the $24 million Lucasys recovery against an acquisition-built monopolist are the models — on hourly, contingency, or hybrid terms, and we have experience working with litigation funders when the economics call for it. And we are independent of the platform giants.

For litigation funders and claim investors. We have advised multiple litigation finance companies on the strength and risks of potential antitrust claims — liability theories, market definition and damages, evidentiary considerations, and the litigation-risk factors that drive funding decisions. We understand how funders underwrite antitrust, and we deliver assessments in the form an investment committee can use.

Frequently asked questions

Does our fund need an HSR filing for this add-on? It depends on three things: the size of the transaction (the 2026 threshold is $133.9 million); for mid-size deals, the size of the parties; and the exemptions and aggregation rules, which decide how holdings are counted across funds and associates and whether rollover equity and side investments count toward the deal value. Those rules trap sophisticated parties every year, so we give reportability answers quickly — often on a fixed fee. Two cautions: a non-reportable deal can still be investigated and challenged, and several states now require filings of their own.

Can a sponsor be liable for a portfolio company’s antitrust violation? Courts have treated a sponsor and its majority-owned portfolio company as a single enterprise that cannot conspire with each other under Section 1 — but the same control is what exposes a sponsor under Section 7, Section 8, and the HSR Act, and the FTC has pursued a sponsor directly for a portfolio company’s acquisition strategy, ultimately by consent order. Whether funds that design and finance a roll-up should bear liability for its effects is now an active academic and enforcement debate. The practical answer is that sponsor-level conduct — board appointments, information flows, deal strategy, and filings — is where the exposure lives, and it can be managed.

Our add-ons are each too small to report. Is there really antitrust risk? Yes. Section 7 applies to every acquisition regardless of size, Section 2 reaches a pattern of acquisitions that builds or maintains monopoly power, the agencies asked the public in 2024 to identify serial-acquisition strategies, and private plaintiffs — including cities in the fire-apparatus litigation — are now bringing acquisition-monopoly cases. Sub-threshold means unreviewed, not immune. A market-by-market screen before the next deal is inexpensive insurance.

One of our partners sits on two portfolio boards in related businesses. Is that a problem? It may be. If the companies compete and exceed the Section 8 thresholds ($54,402,000 in capital, surplus, and undivided profits for 2026, subject to de minimis exceptions), the agencies’ position is that the interlock is unlawful even if the sponsor appoints different individuals to each board. Board observers and LLC structures are not reliable safe harbors, and the agencies have obtained resignations at private-equity-owned companies without filing a case. We audit portfolio boards and fix interlocks quietly.

A portfolio company received a class notice in a price-fixing case. Should it opt out? Sometimes. Large purchasers with well-documented purchases and strong claims often recover more through a direct action than through the class, and the decision has a deadline. We evaluate the economics — volume, overcharge evidence, the defendants’ solvency, the cost and timeline of a direct action — and explain the trade-offs before the window closes.

A portfolio company believes a dominant supplier or platform is squeezing it. What now? Start with an independent evaluation. We assess the liability theory, market definition, antitrust injury and damages, the evidence, and the defendant’s durability and we tell you plainly whether the claim is worth pursuing. If it is, we can bring it on hourly, contingency, or hybrid terms, or work with a litigation funder.

Do you work with litigation funders? Yes, on both sides of the relationship. We have advised multiple litigation finance companies on the strength and risks of potential antitrust claims, and we have experience working with funders on cases we bring. We understand how funders underwrite antitrust and what an investment committee needs to see.

What does this cost? Reportability answers and routine no-overlap filings can be quoted as fixed fees. Board-seat audits, add-on screens, and claim evaluations are scoped projects with a price we can discuss before we start. Contested reviews and litigation are priced to the matter, with contingency and hybrid structures available for the right claim.

From our writing

For more, browse the blog’s Private Equity category and our legal resources library.

Contact Us
If your fund is planning an acquisition, building a platform, auditing its boards, or sitting on a claim it has not valued, contact Bona Law. We respond quickly.

Related practices and industries

Practices: Mergers & Acquisitions · Antitrust Counseling and Compliance · Antitrust Investigations · Monopolization and Exclusionary Conduct · Antitrust Litigation · Antitrust Class Actions · Distribution, Dealer Termination & Pricing Practices · Labor Antitrust · State Attorney General Antitrust · Appellate Litigation · Complex Commercial Litigation · Lanham Act and False Advertising · Challenges to Anticompetitive Government Action · Antitrust Co-Counsel · California Antitrust & Cartwright Act · Antitrust Opt-Out and Direct-Action Recovery