Dr. Petra Rihar specializes in litigation and arbitration. She represents individuals and companies before state courts and arbitral tribunals in domestic and cross-border disputes, in interim relief proceedings as well as in the recognition and enforcement of foreign judgments. She also advises on national and international commercial, contract and corporate law, labour law and international private law.

Petra Rihar has served as party representative, arbitrator, legal expert and secretary to the tribunal in numerous institutional and ad hoc arbitrations governed by a variety of substantive and procedural laws. Her work experience covers a wide range of industries and contracts, complex cross-border disputes and foreign investments in state infrastructure (investor-state disputes).

Petra Rihar is recommended in her field of work.
Lexology/WWL Arbitration 2024: «Peers and clients say: ‘Petra is a strong and sensible arbitration practitioner’, She is highly communicative with clients’, She always has the knowledge and accuracy needed to win a case’».
WWL Arbitration 2023: «Peers and clients say: ‘She is an excellent practitioner with great knowledge of Eastern European markets’, ‘She has an impressive track record in the industry’».
WWL Arbitration 2022: «Peers and clients say: ‘Petra is an excellent arbitrator’, ‘She combines an extremely quick analytical mind with excellent knowledge of the law’, ‘She is a prominent arbitration mind’, ‘There is a lot to be learned from her’».
WWL Arbitration 2021 – Future Leaders: «Peers and clients say: ‘Petra is a highly experienced arbitration practitioner who is valued for her thorough work, excellent legal knowledge and talent for efficient procedural solutions in complicated situations’, ‘She is excellent arbitrator and counsel’, ‘Petra is an absolutely reliable and highly professional lawyer, with an outstanding work ethic and friendly approach’».
WWL Arbitration 2020 – Future Leaders: «Petra Rihar is ‘an outstanding arbitrator’ who is well acquainted with handling complex commercial and investment-related disputes».
Petra is also recommended in WWL Switzerland 2022, 2023 and 2024.

2020 Partner with LANTER
2013 Partner with law firm in Zurich
2006 Associate and Senior Associate with international law firms in Zurich and London
2006 University of Lucerne, Dr. iur. (magna cum laude)
2006 Columbia Law School, LL.M.
2004 Legal Counsel at The Thomson Corporation, Zug
2004 Admission to the Zurich bar (admitted to all Swiss courts)
2001 Law clerk at the District Court of Zurich and teaching assistant in corporate, banking and securities law, University of Zurich
2000 University of Zurich, lic. iur. (magna cum laude)



Arbitration (institutional and ad hoc, commercial and investment disputes)
Litigation (domestic and cross-border)
Corporate and commercial law
Contract law
Labour law
International private law


Shareholder Disputes Arising From Shareholders’ Agreements, Protection of Minority Shareholders in Multiparty Proceedings Through Emergency Measures and Joinder – Case Study, Austrian Yearbook on International Arbitration 2023, p. 190 et seqq.

Scope and Interpretation of Arbitration Agreements under Swiss Law, ICC Dispute Resolution Bulletin 2021, Issue 2 (June 2021), p. 55 et seqq.

Kluwer Arbitration Blog:


  • Case Analysis of the Swiss Federal Supreme Court Decision 4A_187/2020 of 23 Feb 2021, 1 April 2021

Practical Law Arbitration:

Petra Rihar, Das Einzelunternehmen im Schweizer Privatrecht (The Sole Proprietorship in Swiss Private Law), Luzerner Beiträge zur Rechtswissenschaft, Band 17, Zurich 2007

Petra Rihar, Obseg varstva pravic blagovnih in storitvenih znamk (The Scope of Protection of Trade and Service Marks in Swiss and Slovene Law), 11 Pravnik 717, Ljubljana 1997