In Case 1000, Netanyahu is suspected of having received gifts from businessmen overseas, including cigars for himself.
The case has focused primarily on Netanyahu's relationship with Israeli billionaire and Hollywood producer Arnon Milchan, though the investigation has expanded to include other wealthy businessmen with ties to Netanyahu. Milchan has denied any wrongdoing.
In Case 2000, police have investigated conversations Netanyahu had with Arnon "Noni" Mozes, the owner of one of Israel's leading newspapers, Yedioth Ahronoth, which is regularly critical of the Prime Minister.
In the conversations, transcripts of which have been leaked in the Israeli media, Netanyahu allegedly discusses limiting the circulation of Yedioth Ahronoth's major competitor -- the Sheldon Adelson-owned Israel Hayom, a right-wing newspaper seen as favoring Netanyahu -- in exchange for more favorable coverage.
Both Netanyahu and Mozes have said these were not serious discussions; rather, they each claim they were trying to expose the other's lack of trustworthiness.
Netanyahu has repeatedly proclaimed his innocence, insisting that investigators will find he did nothing wrong.