He was put into jail for a good 8 years.
Here's the wikipedia on him:
http://en.wikipedia.org/wiki/Mikhail_KhodorkovskyJust look at this shit he pulled:
"His bank Menatep, along with other Russian banks, would hold on to government funds for months at a time in order to speculate on exchange rates and other investments, enriching the bank's owners at the expense of the designated recipients of the government funds. Investment tenders were followed by an even more infamous "give-away" of Russian state assets to select business elites—the loans-for-shares program, which introduced the term "oligarch" to describe the handful of beneficiaries. In the loans-for-shares auctions, the auctioneers were often the same as the bidders—the auctions were rigged and the state knew it. It was during this period that Khodorkovsky acquired the Yukos oil company for about $300 million through a rigged auction. Khodorkovsky subsequently went on a campaign to raise investment funds abroad, borrowing hundreds of millions. When the 1998 financial crisis struck Russia, Khodorkovsky defaulted on some of his foreign debt and took his Yukos shares offshore to protect them from creditors.[13]"
That [13] is "Hoffman, David (2002). The Oligarchs: Wealth and Power in the New Russia. New York: PublicAffairs. pp. 100–126."
Or this:
"In a Foreign Affairs article on the situation in 1998–99, Lee Wolosky, a former counterterrorism official under the Clinton administration, detailed how Yukos "managed to siphon off some $800 million during a span of approximately 36 weeks" in 1999 through transfer pricing, forcing Yukos' Russian subsidiaries to sell oil at a fraction of world market prices to the holding company. Wolosky also described how Khodorkovsky had engaged in massive asset stripping of Yukos subsidiaries following the 1998 financial crisis:
After three international banks acquired approximately 30 percent of Yukos following a default on a loan to an affiliated bank, Khodorkovsky sought to turn Yukos into an empty shell. He forced it to convey its most significant asset – its controlling position in oil production subsidiaries – to unknown offshore entities. At the same time, he attempted the mother of all share dilutions: by transferring a massive number of new shares to offshore entities he is believed to control.[26]
According to Wolosky, Khodorkovsky and his colleagues, unsatisfied, continued the looting "more directly—by stealing valuable assets, including wells, equipment, and anything else that can be found on an oil field", and between 1997 and 1998, Yukos had plundered $3.5 billion worth of assets. Wolosky further blamed Khodorkovsky to be complicit in two contract killings between 1998 and 1999:
In June 1998, the mayor of Nefteyugansk was murdered. That spring, he had led a very public crusade and hunger strike against Yukos, protesting the enormous wage and tax arrears that he argued were impoverishing the region ... The mayor had previously sent a secret cable to Prime Minister Sergey Kiriyenko requesting his assistance in the showdown. But the mayor was found dead before Kiriyenko could answer.[26]"
[26] is "Wolosky, Lee S. (March–April 2000). "Putin's Plutocrat Problem". Foreign Affairs 79 (2): 18–31. JSTOR 20049638."
He was one of the most powerful oligarchs in Russia, and Putin has showed the Russian oligarchs what can happen to every single one of them.