Luhan, a member of K-pop boy band EXO, became the third Chinese idol to launch a legal battle against his label SM Entertainment, spawning speculation over the reasons behind their defections.
Luhan filed a lawsuit against SM and its chief executive Kim Young-min, demanding the termination of the contract he signed with the nation's largest talent agency in 2010.
The exact reason for the lawsuit was not publicly revealed.
K-pop insiders, however, speculate that the legal action resulted from mistreatment, as was the case with former EXO member Kris. Kris also sued SM on May 15 to nullify his contract, taking issue with what he claimed was unfair treatment.
SM released an official statement saying, "We are perplexed by the sudden legal action by Luhan. He expressed his intention to … focus on his solo activities in China rather than group activities, so we were discussing the future plans."
"It is likely that, upon gaining immense popularity through EXO, he is putting his own good ahead of the group activities," it stated.
Prior to the filing, Luhan had been mostly absent from the entertainment scene, citing health issues. The singer did not participate in EXO's first concerts in Bangkok on Sept. 13 and 14.
Luhan is the latest of a handful of Chinese idols in the K-pop scene who have waged legal battles to end their contracts.
Former EXO member Kris demanded that his contract be revoked on May 15, and former Super Junior member Hankyung sued the label in late 2009. All of them cited tight schedules, unjust distribution of profit and exploitation of basic human rights as the reasons behind their decision to fight SM.
Some K-pop watchers have raised the possibility that the Chinese members could not adjust to the K-pop scene's idol training system. There have long been concerns that foreign trainees could find it hard to adapt to the Korean training system, which involves cramming would-be singers into a dorm and putting them through a hectic schedule of demanding practice sessions.
But SM raised speculations that there may be a certain pattern among the Chinese idols.
The company did not specify what the pattern is, but K-pop insiders allege that the idols are following in Hankyung's footsteps. They ask the court to end the contract when they are at the peak of their popularity and move to China to pursue solo activities, the industry watchers said.
In fact, Hankyung signed with the Chinese agency YUEHUA after he won the case against SM to continue his activities as an actor and singer in China. The former idol is reportedly earning more than he did with Super Junior.
Kris also proved that his departure from EXO did not deal a blow to his career. According to local reports, the Chinese-born Canadian is set to sign a contract with Hwai Brothers. He had already won the lead roles in several rom-coms.