During the Cardassian occupation, Ibudan ran the black market between the station and Bajor. He would willingly sell medical supplies for a high price, even to those Bajorans who desperately needed it. A child needlessly died when they could afford to buy the drug that would have saved her life from Ibudan.
In the 2360s, Ibudan killed a Cardassian officer who had wanted a bribe from him to not intefere with his black market trading. Ibudan killed him and he was arrested by Odo and sent to Kran-Tobal prison. During his time there, he spent most of his time with members of the Resistance who were also imprisoned there. One of these prisoners had been arrested for cloning experiments.
When the Occupation ended, the Provisional Government had him released. Using his knowledge of cloning, he created a clone of himself, which he later killed in one of Quark's holosuites when he came to Deep Space 9. With DNA from Ibudan and his clone being identical, suspicion fell on Odo, who possesses no DNA. Ibudan later had his face cosmetically altered to appear as an elderly Bajoran called Lamonay S. Julian Bashir discovered Ibudan's clone was the one who had been killed, just in time to save Odo from an angry mob of civilian residents who demanded Odo be handed over to them. Odo soon discovered the real Ibudan on a Bajoran ship docked at the station and charged him with the murder of his clone. (DS9 episode: "A Man Alone")
Several weeks later, an entire series of murders were committed on Deep Space Nine. When it was found that another shape shifter who called himself Meta had been killing several people on the station, the civilian population once again became suspicious of Odo. Benjamin Sisko was keen to avoid a repeat of the trouble that had erupted among some of the station's civilian population when they believed Odo had killed Ibudan, informing the residents that Odo was not a suspect in the murders since Odo could be placed at other places when the murders had occurred. (DS9 novel: The Siege)