SIENNA Avocats

What SIENNA Avocats does

Sienna Avocats is an independent French law firm founded in 2022 by Jacques Mazé (formerly of Linklaters LLP) and Bruno Peduzzi (formerly of PwC Société d'Avocats). The firm specializes in two integrated practice areas: corporate law / mergers and acquisitions (covering M&A, private equity, venture capital, corporate restructuring, and management packages) and taxation (covering corporate taxation, personal and estate planning, international taxation, real estate taxation, tax litigation, and fiscal rulings). It serves French and international companies, investment funds, startups, business leaders and managers, and high-net-worth individuals requiring integrated legal and tax counsel on strategic transactions and wealth matters.

The firm operates from a headquarters at 24 avenue Jules Janin in Paris (75116) and a secondary office at 11 rue de Robien in Rennes, with approximately 10 professionals in total (2 founding partners and 8 collaborators). The team is sourced from leading international and French firms and institutions, including Linklaters, PwC Société d'Avocats, Jones Day, Dechert, EY, Fidal, the OECD Centre for Tax Policy and Administration, and Cabinet Racine, and several team members hold teaching positions at the University of Rennes I. Sienna Avocats has handled marquee cross-border mandates including the €4.9 billion LeasePlan-ALD merger and the €700 million DP World port restructuring, alongside a portfolio of mid-market French M&A, venture capital, and build-up transactions (including 40+ veterinary clinic sales to consolidating groups between 2022 and 2025).

The business model is professional services billing, with fees set transparently and adjusted to the stakes and complexity of each matter; pricing is not publicly disclosed and prospective clients are directed to contact the firm for quotes. The go-to-market is relationship-driven, relying on referrals from accountants, wealth managers, notaries, banks, family offices, and other law firms in France and internationally, complemented by direct business development by the partners and a professional website showcasing team expertise, practice areas, and recent transactions. No public funding rounds, external investors, or parent company relationships are reported, and the firm operates as a founder-owned partnership.

Name

SIENNA Avocats

Legal name

Sienna Avocats

Website

https://sienna-avocats.com

Company type

Private

Operating status

Operating

Headcount range

1–10 employees

Short description

Sienna Avocats is an independent French law firm founded in 2022, specializing in corporate M&A and tax advisory. Based in Paris and Rennes with approximately 10 professionals, it serves French and international companies, investment funds, startups, executives, and high-net-worth individuals.

Ownership category

akta.pro rank

Headquarters

HQ city

Paris

HQ country

France

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Others

Revenue model

1. Legal Advisory Services: The firm generates revenue by providing legal advisory services to companies, investment funds, startups, directors, and individuals. Services include corporate/M&A transactions, private equity deals, venture capital financing, tax advisory, and wealth structuring. Billing is based on transparent fees adjusted to each matter's stakes.

Pricing tiers

Go-to-market motion1 record

Distribution channels1 record

Marketing channels3 records

Core offering

SIENNA Avocats is an independent French law firm providing integrated legal and tax advisory in business law and taxation. The firm advises companies, investment funds, startups, executives, and individuals on mergers and acquisitions, private equity transactions, venture capital financing, corporate restructuring, tax planning, and wealth structuring. It combines corporate/M&A and tax expertise under one roof with direct partner involvement in every matter.

Product overview

Sienna Avocats is an independent French law firm specializing in business law and taxation. The firm offers two complementary core practice areas: Corporate M&A (covering mergers, acquisitions, private equity, and venture capital) and Tax Law (covering corporate taxation, personal estate planning, international taxation, and tax litigation). These practice areas work together to provide comprehensive advisory services for businesses, investment funds, startups, and individuals.

Differentiator

Problem solved

Functional benefit

Products and services

• Corporate M&A / Fusions-Acquisitions Legal advisory for mergers, acquisitions, divestitures, corporate restructuring operations, private equity transactions, venture capital financing, and management packages, for companies, investment funds, and startups.
• Fiscalité (Tax Law) Tax advisory covering corporate taxation, personal and estate planning, international taxation, real estate taxation, tax litigation, fiscal rulings, and wealth structuring for companies, executives, and individuals.

Quantifiable outcome

• Over 40 veterinary clinic transactions completed between 2022-2025
• +1 more outcomes

Named customers20 records

Segments4 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Partnerships

One partnership is on record.

• Professional Advisory Network (unspecified)minorOthersSIENNA Avocats has established close relationships with specialized professionals in France and internationally, including financiers, investment banks, accountants, family offices, wealth managers, notaries, and lawyers in other specialties or jurisdictions. This network allows the firm to compose agile and complementary teams to efficiently respond to client needs.

Scale indicators1 record

Recent moves6 records

Expansion highlights5 records

Direct peers

• Jeantet: Mid-size French full-service law firm with strong M&A, private equity, and tax practices. Similar boutique-style positioning serving French mid-market and PE clients with overlapping practice areas to SIENNA.
• Taj (Deloitte Société d'Avocats): Deloitte's French law firm arm providing M&A, tax, and corporate legal advisory. Competes with SIENNA for mid-market French transactions and tax advisory mandates, particularly for PE-backed and corporate clients needing integrated services.
• Sekri Valentin Zerrouk: French M&A boutique law firm specializing in mid-market corporate transactions, private equity, and venture capital. Directly comparable to SIENNA's M&A practice; Floriane Barre joined SIENNA from this firm in 2023, indicating active competition for talent.
• August Debouzy: French business law firm with strong M&A, private equity, and corporate practices, with similar boutique positioning in the French mid-market. Directly competes for M&A and corporate advisory mandates in the same client segment as SIENNA Avocats.
• Villechenon: French tax boutique law firm specializing in corporate tax, M&A tax, and wealth structuring. Directly comparable to SIENNA's tax practice; Floriane Barre worked at Villechenon before joining SIENNA in 2023.
• Lacourte Raquin Tatar: Prominent French tax boutique law firm specializing in corporate taxation, M&A tax, and transactional tax advisory. Directly comparable to SIENNA's tax practice area and competes for similar tax mandates from corporate and PE clients.
• Fidal: Largest French tax and legal advisory firm with strong corporate, M&A, and tax practices. Competes for tax advisory and corporate legal work; SIENNA hired Océane Joncour from Fidal in 2025, indicating active competition for both talent and clients.

Broad incumbents

• Skadden: Global law firm with a substantial Paris office covering M&A, private equity, and corporate finance. Competes for cross-border mandates involving French companies, overlapping with SIENNA's M&A and PE practice at larger transaction sizes.
• Bredin Prat: Premier French law firm specializing in M&A, corporate finance, and litigation. Significantly larger than SIENNA but operates in the same French M&A market, competing for larger-cap transactions where SIENNA cannot compete.
• Cleary Gottlieb Steen & Hamilton: Global law firm with a major Paris office specializing in cross-border M&A, private equity, and corporate governance. Competes with SIENNA for French elements of large international transactions and has overlap with SIENNA's M&A practice at larger transaction sizes.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/sienna-avocats

Revenue estimate

Valuation estimate

Number of profiles

Profiles9 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about SIENNA Avocats