Mergers and Acquisitions Codes
The joint ABA and LOC M&A codes (MA and MF series), structuring deal work by workstream, with specialist work billed to discipline-specific MF codes and the MF00 no-bill rule.
UTBMS mergers and acquisitions codes structure deal work by the workstreams every practitioner recognizes, from preliminary matters through post-closing disputes.
The set's defining design choice is a split: specialist work bills to specific MF-series task codes by discipline, while generalist deal work bills at the phase level. That split makes specialist cost per deal directly visible, which is exactly where M&A legal spend varies most. The MF00 header is a no-bill rule; specialists code to their specific task codes, never to the header. Every code is searchable alongside all sets at the UTBMS code database.
M&A is episodic, high-value, and specialist-heavy, which makes per-discipline cost visibility the core question, and that is what a legal spend management program builds here: seeing regulatory, tax, IP, and other specialist costs as distinct lines rather than a single deal fee.
What are mergers and acquisitions codes used for?
M&A codes classify deal work two ways at once. Generalist corporate work is coded at the phase level as the deal moves from preliminary matters through diligence, negotiation, and closing. Specialist work is coded to discipline-specific MF task codes so that regulatory, tax, IP, and other specialist streams are visible on their own.
The most important review signal is the MF00 rule. The standard directs that no time be recorded at MF00, the specialty header; specialists must code to their specific MF task codes. Any MF00 volume is a coding error the standard itself prohibits.
What does each M&A code cover?
MA00: Preliminary MattersABA/LOC (2016)
Letters of intent, confidentiality and exclusivity agreements, break fee arrangements, information memoranda, and auction process work.
When to use this code: Use for pre-agreement deal work.
Patterns reviewers commonly see: Preliminary phase cost on deals that die early, which is the natural cost of deal flow but deserves portfolio tracking.
What invoice review checks: Preliminary spend on dead deals as a portfolio ratio; it prices your deal pipeline's legal cost.
MB00: Purchase/Merger AgreementABA/LOC (2016)
Drafting, negotiating, and amending the purchase or merger agreement, including specialist input on terms.
When to use this code: Use for the principal agreement workstream.
Patterns reviewers commonly see: Turn volume on provisions with settled market positions, the P500 pattern at deal scale.
What invoice review checks: Rounds per agreement and hours per turn, benchmarked across comparable deals.
MC00: Due Diligence and Disclosure SchedulesABA/LOC (2016)
Document review, management presentations, diligence questionnaires, data room setup, and disclosure schedule negotiation.
When to use this code: Use for generalist diligence; specialist diligence belongs in the MF codes.
Patterns reviewers commonly see: Diligence staffing and scope unanchored to deal risk profile, and disclosure schedule cost hidden inside general diligence.
What invoice review checks: Diligence cost as a percentage of deal value across the portfolio, with the MF split showing where specialist depth went.
MD00: Ancillary DocumentsABA/LOC (2016)
Drafting and negotiating agreements ancillary to the principal agreement.
When to use this code: Use for ancillary document work.
Patterns reviewers commonly see: Standard ancillaries billed at bespoke drafting depth.
What invoice review checks: Hours per ancillary against the firm's precedent bank, the P400 pattern.
ME00: FinancingABA/LOC (2016)
Drafting and negotiating acquisition financing, including loans, debentures, equity financing, and security agreements.
When to use this code: Use for acquisition financing work.
Patterns reviewers commonly see: Financing counsel and deal counsel overlapping on the same documents.
What invoice review checks: The lender-counsel versus company-counsel division defined at engagement.
MF00: Regulatory and Specialty Matters (phase header)ABA/LOC (2016)
Header for specialist workstreams. The standard directs that time should NOT be recorded at MF00; specialists bill their specific MF task codes.
When to use this code: Never bill here; use MF10 through MF80.
Patterns reviewers commonly see: Any MF00 volume, which the standard itself prohibits.
What invoice review checks: MF00 usage is a per-se coding error, one of the few automated rules a standard hands you directly.
MF10: Antitrust/CompetitionABA/LOC (2016)
Filing requirement analysis, competition filings, and responses to regulator information requests.
When to use this code: Specialist code for competition work.
Patterns reviewers commonly see: Second-request responses without phase budgeting, since they can dwarf the rest of the deal's legal cost.
What invoice review checks: Competition spend per filing jurisdiction, with second requests budgeted as their own event.
MF20: Data Security/Privacy/CybersecurityABA/LOC (2016)
Privacy and security diligence, risk and maturity assessment, and related deal terms.
When to use this code: Specialist code for data and cyber work.
Patterns reviewers commonly see: Cyber diligence scope defaulting to full assessment regardless of target data profile.
What invoice review checks: Scope tiering by target data sensitivity, decided at diligence planning.
MF30: Employment, Labor and Employee BenefitsABA/LOC (2016)
Human resource issues in the transaction, including WARN analysis and benefits matters.
When to use this code: Specialist code for employment and benefits work.
Patterns reviewers commonly see: Overlap with MF31 on executive matters.
What invoice review checks: The MF30 and MF31 boundary applied consistently within the deal.
MF31: Executive CompensationABA/LOC (2016)
Employment agreements, severance, equity awards, change-in-control payments, and retention arrangements.
When to use this code: Specialist code for executive compensation.
Patterns reviewers commonly see: Per-executive analysis cost varying widely for similar arrangements.
What invoice review checks: Cost per executive package analyzed, a clean unit benchmark.
MF40: EnvironmentalABA/LOC (2016)
Environmental diligence, permit transfers, and related matters.
When to use this code: Specialist code for environmental work.
Patterns reviewers commonly see: Full environmental workups on low-footprint targets.
What invoice review checks: Scope against the target's actual environmental profile.
MF50: Intellectual Property and TechnologyABA/LOC (2016)
IP and technology diligence, licenses, and IP transfer documents.
When to use this code: Specialist code for IP work.
Patterns reviewers commonly see: IP diligence duplicating portfolio analyses the client already holds (TR720 and patent portfolio work).
What invoice review checks: Reuse of existing portfolio intelligence in deal diligence.
MF60: Real PropertyABA/LOC (2016)
Real property diligence, transfer documents, and lease assignments.
When to use this code: Specialist code for real property work.
Patterns reviewers commonly see: Overlap with the standalone real estate code sets when property work dominates the deal.
What invoice review checks: Which coding regime governs, decided at matter opening.
MF70: Securities Regulatory MattersABA/LOC (2016)
Registration statements, proxy statements, reports, and no-action requests.
When to use this code: Specialist code for securities work.
Patterns reviewers commonly see: Disclosure document cost spread across many timekeepers.
What invoice review checks: Hours per filing type against comparable transactions.
MF80: TaxABA/LOC (2016)
Transaction structuring, tax diligence, and negotiation of tax allocations and indemnities.
When to use this code: Specialist code for tax work.
Patterns reviewers commonly see: Structuring cost recurring on repeated deal patterns, the P300 pattern.
What invoice review checks: Declining structuring cost on repeat structures.
MG00: Shareholder/Board MattersABA/LOC (2016)
Board presentations, minutes and resolutions, and shareholder approvals.
When to use this code: Use for governance workstream of the deal.
Patterns reviewers commonly see: Full-team attendance at board sessions, the B260 pattern at deal rates.
What invoice review checks: Attendance against an agreed staffing plan for board events.
MH00: Closing MattersABA/LOC (2016)
Closing documents, certificates, legal opinions, closing agenda, and closing execution.
When to use this code: Use for closing work.
Patterns reviewers commonly see: Closing-week surges reflecting deferred work, the P600 pattern.
What invoice review checks: Closing cost per deal size and the surge pattern by firm.
MI00: Integration MattersABA/LOC (2016)
Post-closing integration, including subsidiary restructuring and asset transfers.
When to use this code: Use for integration work.
Patterns reviewers commonly see: Integration continuing indefinitely on the deal matter, the P700 pattern.
What invoice review checks: An integration end date, with later work opened as new matters.
MJ00: Post-Closing Requirements, Disputes and AdjustmentsABA/LOC (2016)
Working capital adjustments, indemnification claims, and earn-out matters.
When to use this code: Use for post-closing adjustment and dispute work.
Patterns reviewers commonly see: Adjustment disputes escalating without an economics check against the amounts at stake.
What invoice review checks: Dispute cost against the adjustment value in play, the L470 logic applied to deals.
MK00: Deal ManagementABA/LOC (2016)
Non-clerical project management overseeing the transaction.
When to use this code: Use for deal management, the M&A counterpart of P100.
Patterns reviewers commonly see: Deal management as an outsized share of total fees.
What invoice review checks: MK00 percentage of deal fees across comparable transactions.
How should legal departments use mergers and acquisitions codes in invoice review?
M&A review is about making specialist cost visible and keeping the coding clean. Track each specialist MF discipline as a share of total deal cost across comparable transactions, since that is where deal spend varies most, and treat any volume coded to the MF00 header as a per-se error to correct.
Capturing the generalist-versus-specialist split cleanly depends on the eBilling system enforcing the MF structure, which is where legal technology implementation matters: the MF00 no-bill rule and per-discipline specialist coding should be system-enforced so specialist cost per deal is reliable.
How do Mergers and Acquisitions Codes support legal spend management?
Mergers and Acquisitions Codes only deliver value inside a program that enforces them. Our legal spend management and enterprise legal management hubs cover how coded invoices become spend control, and our guides to matter budgets, outside counsel spend benchmarks, and outside counsel rate negotiation go deeper on the review programs, guidelines, and eBilling rules that put UTBMS coding to work.
Bottom Line
The M&A set is designed to answer one question that matters most in deal spend: what did the specialists cost. By splitting generalist phase work from discipline-specific MF codes, it makes regulatory, tax, and IP cost per deal directly visible. The MF00 no-bill rule is the discipline that keeps that split clean.
Bill specialists to their MF task codes, never to MF00, and M&A spend resolves into the per-discipline costs that actually drive deal fees.
Frequently asked questions
What are UTBMS M&A codes used for?
They structure merger and acquisition deal work by workstream, from preliminary matters through post-closing disputes. Generalist corporate work bills at the phase level, while specialist work bills to discipline-specific MF task codes, which makes specialist cost per deal directly visible.
What is the MF00 no-bill rule?
MF00 is the specialty header, and the standard directs that no time be recorded to it. Specialists must code to their specific MF task codes instead. Any volume billed to MF00 is a coding error the standard itself prohibits, so it is a per-se flag in review.
Why does the set split generalist and specialist work?
M&A legal spend varies most in its specialist streams: regulatory, tax, IP, and similar. Coding generalist work at the phase level while routing specialist work to discipline-specific MF codes makes that variation visible, so a department can see and compare what specialists cost per deal.
How should M&A codes be used in invoice review?
Track each specialist MF discipline as a share of total deal cost across comparable deals, and treat any MF00 volume as an error to correct. Each code below lists the patterns reviewers commonly see and what invoice review checks.
How do UTBMS codes relate to outside counsel billing guidelines and legal spend management?
UTBMS codes are the shared vocabulary that outside counsel billing guidelines and a legal spend management program depend on. Guidelines define what each code should and should not contain, the eBilling system enforces those rules, and consistent coding is what makes spend analytics and cross-firm benchmarking possible. Without agreed codes, guidelines cannot be enforced and spend data cannot be compared.
About this reference
UTBMS code sets are standards published by their respective bodies, including the ABA, the LEDES Oversight Committee, UTBMS.com, the CBA, DRI, the Judiciaries of England and Wales, and the Yerra Global KM Expert Group. All copyrights and trademarks are the property of their respective owners; Swiftwater & Company is not affiliated with or endorsed by any of them.
Code identifiers follow the published standards, while all descriptions and annotations are original Swiftwater commentary, developed with human expertise, proprietary consulting knowledge, and AI assistance.
This is general reference material, not legal advice. Standards are revised over time, so confirm the current version with the originating body before implementing.
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