Mikhail Prokhorov must be wondering what on earth he did to draw the ire of Russian President Vladimir Putin. He's a quiet billionaire who doesn't seem to tread on anyone's toes. It's true he did run against the president in the 2012 presidential election, but it was generally considered to be a mutually agreed staged attempt to convince the world there was an opposition, and since then the 50-year-old businessman has barely muttered a political word.

But, as Putin spent hours answering questions from across the country in his recent televised Q&A session, officers of the Federal Security Bureau (FSB) and tax inspectors were conducting raids on several of Prokhorov's businesses including the Moscow headquarters of his holding company, Onexim Group, his investment firm Renaissance Capital, the power generating company Quadra, and the International Financial Club (IFC) bank.

The raids were apparently part of an investigation into another bank that IFC had bailed out last year and Onexim had a stake in, but the "Moscow Times" reported the FSB as saying that it had found tax law violations at "a number of commercial structures" although it didn't say exactly which ones.

Ghost of Khodorkovsky

This tactic has a familiar ring to it - one which must have sent a shudder down Prokhorov's spine as he recalled the fate of the oligarch, Mikhail Khodorkovsky, who spent 10 years in prison on tax fraud and embezzlement charges after falling foul of the Kremlin.

Rumors about what he could have done to bring this upon himself have run rife - but the one that seems to be congealing best is that the Kremlin wants his media holdings, RBC - which has TV, print and online interests. According to its 2013 annual report, RBC had considerable debts, about $208 million (185 million euros), but it has influence, and, in a sea of otherwise bland and controlled media outlets, it is one of the most liberal, and that may have been its Achilles heel.

Its print version was the only daily newspaper to dedicate its whole front page to the Panama papers and the alleged involvement of people close to Putin's inner circle in money laundering schemes. It was a point not lost on the vitriolic head of Russia Today who, in his own TV program, intimated that RBC was acting as a stooge for US interests.

"The Americans have helpers around the world, and Russia is no exception - people who are prepared to link Putin personally to offshore companies in whatever way they can."

Bigger fish?

So there's a reason, but is there a bigger fish to be had? Onexim owns a majority stake in RBC, but its more lucrative investment is Renaissance Capital, an investment bank that focuses on emerging markets. In the first half of 2014 it reported an 81 percent year-on-year increase in its net profit to $8.7 million, up from $4.76 million for the same period in 2013. Onexim is a private investment fund with a portfolio that focuses on mining, financial services, real estate, media, utilities and technology. It owns shares in the bank VTB, several billions of dollars worth of the potash company, Uralkali, and at the time of launching in 2007 has assets estimated to be worth $17 billion - including a large stake in Norilsk Nickel, one of the world's largest nickel producers.

Privatizing that pool would be a much more interesting proposition for a cash-strapped treasury. And it seems the government has multiple interests in acquiring a variety of businesses at the moment, including one of Moscow's largest and privately owned airports, Domodedovo. One of its owners, Dmitry Kamenshchik, is under house arrest awaiting a trial for alleged security violations at the airport that allowed terrorists to carry out a bombing in 2011 which killed 37 people. It's not unreasonable to investigate the possible laxness of security, but questions about the timing and motivations behind of the arrest of Russia's 27th most wealthy man abound, with many analysts saying it's little more than a crude attempt to get him to cede control to a Kremlin friendly organization - like say, Gazprom.

Further down the food chain, but also sending an unsettling message to anyone wanting to invest in Russia, is a court case involving Ikea. Like Prokhorov, its offices were also raided last week by officers looking for documents for a case that has been brought against the Swedish company over the 16 hectares of land it acquired from an agricultural consortium, and which it turned into a mega store back in the early 2000's.

The group's leaders say their signatures were forged and they now want their land back. Ikea maintains the deal was above board and is cooperating with the investigation. But the fact that these types of raids - whether they be for tax or any other reasons - are happening with seemingly increasing regularity must set alarm bells off for any prospective companies looking to invest in Russia. And as for the oligarchs - they must be wondering for whom the bell will toll next.