Conflicts of interest: the checks that can kill a deal before it starts

A partner at a major firm gets a call: a private equity client wants representation on a $400 million acquisition. Before anyone opens a document, an associate runs the target's name, its subsidiaries, its board members, and the deal counterparties through the firm's conflicts database. Three hours later, the answer comes back: the firm represented the target's parent company in a licensing dispute eight years ago, and that engagement is still technically "open" because a file was never formally closed. The new matter is dead before it started. This is not bureaucratic caution. It is a legal requirement, and getting it wrong can mean disqualification, malpractice exposure, or bar discipline.

Why conflicts checks exist

A conflict of interest arises when a lawyer's duty to one client could compromise the duty owed to another, current or former. Law firms are fiduciaries: they owe undivided loyalty and strict confidentiality to each client. Representing two parties with adverse interests, even in unrelated matters, can breach that duty.

In the US, the controlling framework is the ABA Model Rules of Professional Conduct, specifically Rule 1.7 (concurrent conflicts) and Rule 1.9 (duties to former clients). The American Bar Association (ABA) writes these as model rules; each state bar adopts its own version, often with variations, and state bars are the actual enforcement bodies. New York, California, and Texas each have their own disciplinary rules that firms operating nationally must reconcile.

In England and Wales, the Solicitors Regulation Authority (SRA), the regulator for solicitors, enforces the SRA Standards and Regulations, which include a specific Conflict of Interest rule barring firms from acting where there is a conflict or significant risk of one. Across the EU, national bar associations set analogous rules, often built on the Council of Bars and Law Societies of Europe (CCBE) Code of Conduct, a shared ethical baseline for cross-border legal practice.

The two core conflict types every professional should recognize

Concurrent conflicts. The firm currently represents Client A and is asked to take on Client B, where B's interests are directly adverse to A's, or where representing B would be "materially limited" by duties to A. Classic example: a firm cannot represent both the buyer and seller in the same transaction, even if both parties are amenable, unless strict conditions are met.

Former client conflicts. Under Rule 1.9, a lawyer cannot represent a new client against a former client in the same or a "substantially related" matter, if the new representation would use confidential information from the old one. This is why conflicts checks reachreachLe nombre de personnes uniques exposées à votre message sur une période donnée. Contrairement aux impressions, le reach compte chaque personne une seule fois, quel que soit le nombre d'expositions.Voir la définition complète → back years, sometimes decades. A firm's institutional memory of a client relationship does not expire when the last invoice is paid.

There is also the imputed conflict: under Rule 1.10, one lawyer's conflict is imputed to the entire firm. If any partner at a 2,000-lawyer firm has a disqualifying conflict, the whole firm is typically barred, not just that individual, unless an ethical wall (an internal information barrier separating the conflicted lawyer from the matter team) is properly implemented and disclosed.

Waivers: how firms navigate around conflicts

Not every conflict is fatal. Clients can consent, in writing, after full disclosure. This is called an informed consent waiver. Large firms increasingly ask major clients to sign advance waivers at the outset of the relationship, agreeing in principle to let the firm represent other clients in unrelated future matters, even adverse ones, subject to conditions.

Courts scrutinize these waivers unevenly. Some enforce broad advance waivers between sophisticated corporate clients (see the reasoning in *Galderma Labs v. Actavis*, a frequently cited US case on advance waiver enforceability). Others strike them down as insufficiently specific. The ABA's own guidance, Formal Opinion 05-436, addresses when advance waivers are valid; it is a useful primer for anyone wanting the underlying reasoning (available via the ABA's ethics opinion archive).

Some conflicts cannot be waived at all: for example, representing directly adverse parties in active litigation before the same tribunal, where a lawyer's duty of loyalty is irreconcilable regardless of consent.

What the intake process actually checks

Before opening any matter, firms run a conflicts check through a conflicts database that cross-references:

• The new client's name, subsidiaries, parent companies, and known affiliates
• Adverse parties named in the matter
• Directors, officers, and major shareholders where relevant (for M&A and litigation work especially)
• Every lawyer at the firm, including laterals who joined from other firms bringing prior client relationships with them

This is not a formality. Lateral hiring, a partner moving from Firm A to Firm B, is one of the biggest conflict triggers in the industry, because the incoming partner's client list must be checked against every existing matter at the new firm. Big firm mergers can also implode over unresolvable conflicts between the two firms' client rosters.

Firms increasingly use dedicated conflicts management software (vendors like Intapp are widely used in the sector) that flags fuzzy name matches, subsidiary structures, and historical matter data automatically. But software flags candidates; a conflicts counsel or ethics committee makes the judgment call.

The cost of getting it wrong

Failure to catch a conflict can result in:

• Disqualification: a court removes the firm from a case mid-litigation, sometimes after months of billed work, which is also a reputational blow.
• Malpractice liability: the harmed client sues for breach of fiduciary duty.
• Fee disgorgement: courts have ordered firms to return fees earned on a conflicted matter, even absent proven harm.
• Bar discipline: sanctions ranging from reprimand to suspension of the individual lawyer's license.

A well-known cautionary pattern: firms that skip proper conflicts checks during rapid growth or after a merger. The DOJ and courts have disqualified firms in high-stakes antitrust and patent litigation specifically over inadequate conflict screening, underscoring that this is an operational risk with real financial teeth, not just an ethics footnote.

In-house counsel and cross-border complexity

For in-house lawyers, conflicts logic works differently but matters just as much: a general counsel evaluating outside firms must ask whether that firm's other clients create risk, particularly in industries with few major players (aerospace, pharma, large-cap banking) where the same handful of firms cycle through every deal.

Cross-border matters compound the difficulty. A conflict rule that is waivable in New York may be unwaivable under the SRA's stricter regime in London, or under a civil law jurisdiction's bar rules in Germany or France, where some conflict categories are treated as absolute prohibitions rather than waivable risks. Firms with offices across jurisdictions must apply the strictest applicable rule to stay safe, which is why global firms often maintain a single centralized conflicts function rather than letting each office self-police.

🎬 [VIDEO: "Conflicts of Interest in Law Firms Explained" — youtube.com — search for law firm ethics training content from bar associations or major law schools covering Model Rule 1.7 and 1.9 mechanics]

Key Takeaways

• Conflicts checks are a legal and ethical requirement, not administrative overhead: ABA Model Rules 1.7 (current clients) and 1.9 (former clients) in the US, and SRA Standards and Regulations in England and Wales, govern them, enforced by state bars and the SRA respectively.
• A conflict at one lawyer is typically imputed to the whole firm (Rule 1.10), unless a properly disclosed ethical wall is in place.
• Clients can waive many conflicts through informed consent, including advance waivers, but courts scrutinize these unevenly and some conflicts (like directly adverse representation in the same litigation) cannot be waived at all.
• Lateral hires and firm mergers are high-risk conflict triggers because incoming lawyers bring their prior client relationships with them.
• Getting it wrong carries real consequences: disqualification from a matter, fee disgorgement, malpractice liability, and bar discipline, making conflicts clearance a genuine gatekeeping function before any billable work begins.