Shedding In-Group Mentality and Embracing a 'Winning Mindset': Sejong Transforms [Invest&Law]

Oh Jonghan, 38-Year Sejong Veteran
Raised Revenue by 93% in Just Five Years
Achieved 436.3 Billion Won Last Year, Soaring to Third Place
Bold Recruitment of “Star Lawyers” in Each Field
Simply Increasing Headcount Does Not Make a Firm

O Jonghan, Representative Lawyer of Sejong Law Firm, is being interviewed by The Asia Business Daily on the 30th at Sejong Law Firm in Jongno-gu, Seoul. Photo by Jinhyung Kang

This year, among the major law firms, Sejong Law Firm is undoubtedly creating the most dynamic upheaval. In just five years, the firm increased its revenue by a remarkable 93%, shaking up the stagnant hierarchy of law firm earnings. In 2023, Sejong broke through the “3 trillion won” barrier with 319.6 billion won in revenue, and last year achieved a record 436.3 billion won, catapulting itself from fifth to third place in the industry (based on 2024 revenue), just behind Kim & Chang and Bae, Kim & Lee.

At the center of this bold growth is Managing Partner Oh Jonghan (18th class of the Judicial Research and Training Institute), who has been with Sejong for 38 years since joining in 1989. Since taking office in 2021, he broke Sejong’s long-standing insular tradition and decisively invested in “star lawyers” from various fields, integrating them into the firm like a black hole. As a result, Sejong secured mega-deals worth trillions of won and handled high-profile cases. The firm successfully advised on major deals such as the merger of HD Hyundai Heavy Industries and HD Hyundai Mipo Dockyard (combined market capitalization of 65 trillion won), the establishment of an Aliexpress-Shinsegae Group online platform joint venture (6 trillion won), and the sale of SK Ecoplant’s environmental subsidiaries, including Renewus (1.78 trillion won). Ongoing work includes SK Innovation’s transfer of its renewable energy business unit to KKR (1 trillion won), the acquisition of Blue Bottle, and advisory on the sale of Kakao Games—all handled by Sejong.

Sejong’s presence is also unrivaled in high-stakes corporate disputes and responses to new industry regulations. In the personal data protection field, the firm handled not only SKT and KT cases but also recently took on the high-profile Coupang data breach incident. Sejong represents the Youngpoong–MBK alliance in the industry’s most talked-about Korea Zinc management dispute. The Asia Business Daily recently met Managing Partner Oh—who is drawing a new blueprint as the “overwhelming No. 2 challenging for the top spot”—at Sejong’s Gwanghwamun office. The following is a Q&A.

-Over the past five years, your revenue has grown dramatically. What was the key driver?

▲In the past, Sejong was a highly insular organization. However, in recent years, we boldly invested in essential outside talent for the future, and as these new members synergized with existing ones, the firm transformed into an open and dynamic organization. Significant internal changes also occurred. A sense of confidence—“we can do it too”—and a kind of ‘winning mindset’ took root among members. In the recent Chambers Asia-Pacific 2026 evaluation, our focus areas—tax, litigation, and international dispute—were newly promoted to Band 1. There is great satisfaction when clients recognize that our organizational capabilities are visibly strengthening.

-You have emphasized qualitative change and organizational reform to achieve 500 billion won in revenue this year. Have there been achievements in the first half?

▲It is important to quickly detect changes in industry and market trends and proactively develop client demand. We are also focusing on service differentiation based on client feedback. Starting in 2024, Sejong has been operating a full-scale client feedback system. Previously, client opinions were heard through individual cases or responsible attorneys, but now we have established a regular and systematic communication channel. We will continue to enhance our integrated consulting capabilities through one-team collaboration and focus on organizational reform.

-When headcount grows rapidly, growing pains often follow. What efforts have you made to strengthen organizational cohesion?

▲Simply increasing headcount does not automatically create a strong organization. If people work in silos or young lawyers are denied growth opportunities, the structure can collapse like a house of sand. We pay close attention to “on-boarding and building a collaborative system.” Recruiting excellent talent is just the starting point. Sejong has established a system where relevant expert groups, client touchpoints, and various departments come together as one team from the earliest stage to execute projects. By focusing on expanding the capabilities of the entire firm, rather than individual achievements, true qualitative leaps are occurring with the natural activation of cross-selling.

Seo Jonghan, representative lawyer of the law firm Sejong, is giving an interview with The Asia Business Daily at the law firm Sejong in Jongno-gu, Seoul on the 30th. Photo by Kang Jinhyung

-You have set the goal of becoming the “overwhelming No. 2 challenging for the top spot.” Which areas are you focusing on in the second half of the year?

▲Today’s client crises cannot be solved with knowledge from a single legal field. Issues such as regulation, criminal law, fair trade, labor, and intellectual property are intricately intertwined. In other words, victory depends on how quickly and precisely a seamless team of experts from various fields can work together. As demonstrated in the first half, we will further solidify our dominance in traditional mainstays such as M&A and large-scale litigation in the second half. In addition, we are maximizing our “integrated consulting” capabilities to proactively defend against corporate risks and help generate profits, led by our cyber security group, the newly established AI and Digital Competition Law team, the Trade and Industry Policy Center, and the Defense and National Security team.

-As you approach the end of your second term, how do you want Sejong to be remembered?

▲Our task is to avoid complacency with past achievements and complete qualitative growth by solidifying our foundation. I am determined to achieve “an elevated and standardized level of service quality,” ensuring that Sejong delivers the highest standards no matter who or which team handles a matter. Sejong aspires to be more than just a legal advisor—it seeks to be a strategic partner that solves clients’ complex risks together. With outstanding skill and a strong sense of ethics, we will be remembered by society as a professional organization that earns true client trust as a companion on the right path.

This content was produced with the assistance of AI translation services.