Prior to entering politics, Ahn served as dean of the Graduate School of Convergence Science and Technology at Seoul National University until September 2012.

In the 2017 South Korean presidential election, Ahn ran as a third party candidate, losing to Moon Jae-in and winning 21.4% of the popular vote.

Ahn was born on 26 February 1962, in Miryang, South Gyeongsang Province, while his father was on military service there; he subsequently moved with his family to Busan, where he grew up.

Ahn rejected the offer because, despite AhnLab struggling, selling the company would lead to widespread redundancies[20][21] and might allow a foreign firm to dominate the Korean market.

In 1999, the company began to run a surplus after the CIH virus became widespread in Korea and people needed to buy V3 to protect against it.

Ahn was awarded an Executive Master of Business Administration (EMBA) degree from the Wharton School (San Francisco campus) in 2008.

He then became a professor at KAIST in 2008, and later in the beginning of 2011 became the Dean of the Graduate School of Convergence Science and Technology at Seoul National University.

[12] Since 2006, Ahn had been offered places in the main political parties but was constantly denied any chance to run as an independent due to opposing factions.

[35][full citation needed] Analysts stated that if positioned as an independent, Ahn would attract a degree of support from those disaffected by mainstream political parties in the wake of corruption allegations and continuing policy failures.

[37] Ahn eventually didn't run despite his positive poll ratings[38][full citation needed] instead endorsing Park Won-soon who went on to win the by-election.

[41] On 19 September 2012, at 3 p.m. Korea Standard Time, Ahn held a press conference and announced his intention to run for the 2012 presidential election.

In an address that lasted around 20 minutes, Ahn spent a considerable amount of time explaining how he came to the decision to run for President of the Republic of Korea, quoting the people he had met while exploring his candidacy, who had expressed their desire for a "new politics".

On 23 November 2012, at 8:20 p.m. KST, Ahn announced that he would drop out of the race,[42][full citation needed] endorsing Moon Jae-in, the Democratic United Party presidential candidate.

[54] He labeled the remaining NPAD "anachronistic progressives",[55] and accused contemporary Korean politicians of lacking policies beyond "short-term gimmicks".

[58] In the event, the People Party performed better than anticipated, coming second in party-list voting and winning 38 seats overall, including 23 of the 28 districts in the liberal stronghold of Jeolla.

[61][62] Following the election, Ahn rejected continued calls to regroup with the Minjoo Party, stating that "it would be inappropriate to speak of politically realigning at this point in time".

[65][full citation needed] Despite rapid increase in opinion polling which briefly bypassed Moon Jae-In, Ahn floundered in TV debates that led to his loss finishing third in a field of five total candidates.

The two leaders of the respective parties, Ahn and former presidential contender Yoo Seung-min, pushed forward with the merger which was completed in February 2018.

[68] After losing the race to become Mayor of Seoul in June, Ahn began a hiatus in his political career starting in September 2018 when he moved to Germany to study.

These negotiations ended unsuccessfully in August 2021 due to disagreements on party-level issues such as Ahn's desire for the PPP to change its name to the People Party and method of picking a 2022 candidate.

On 8 May 2022, Ahn declared his bid in the June 2022 South Korean by-elections, running for the Seongnam Bundang District A vacant seat in the National Assembly.

Cheol was notable as the only PPP legislator to stay in the building after every other Assembly member walked out before the impeachment of President Yoon Suk Yeol.

[84] Ahn, who said he was criticized by the party for his vote, said that "The idea that a president responsible for upholding the constitution of the world's 10th largest economy would stage an unconstitutional coup is beyond imagination".

[85] Ahn's foreign policy proposals are roughly similar to that of South Korean conservatives: he calls for a tougher approach towards North Korea,[86] and supports the THAAD system (although initially opposed to it).

[64] Ahn was among the first who opposed the American deployment of the Terminal High Altitude Area Defense system, commonly referred to as THAAD, alongside Moon Jae-in.

"[90] In December 2011, Ahn has expressed his willingness to donate half of his shares in AhnLab for the education of children from low-income families.

However, a statement by the Korea Taxpayers' Association claimed that the "down contract" was in accordance with trade customs and thus not unlawful due to flaws in the local tax law between 1996 and 2005.