It has been nine months since Formula One's former chairman Gerhard Gribkowsky was found guilty of receiving a £27.5m bribe from Bernie Ecclestone and his offshore family trust Bambino. Gribkowsky became F1's chairman through his position as chief risk officer of German bank BayernLB which owned a 46.65% stake in the sport. BayernLB put Gribkowsky in charge of selling its stake and a court in Munich ruled that he received the £27.5m in return for steering the shares into the hands of F1's current owner, the private equity firm CVC which was allegedly Ecclestone's preferred buyer. Gribkowsky was arrested more than two years ago and since then German journalists (as well as some misguided members of the UK media who follow the sports side of F1) have repeatedly proclaimed that Ecclestone would soon be charged.

Nothing has come of this of course and as every day goes by it looks increasingly unlikely that Ecclestone will be charged. He is still under investigation by German prosecutors but if they charged him now they would presumably need to present some new evidence to explain why they didn't do this earlier. It's hard to imagine what that evidence could be since the key facts in the case have been known for a long time as they formed the core of the indictment against Gribkowsky. However, the Germans aren't the only ones investigating Ecclestone and a report in the Sunday Telegraph by Pitpass' business editor Christian Sylt reveals exactly what else he is up against.

In July 2011 Sylt revealed in another exclusive that Ecclestone admits to paying Gribkowsky. However, Ecclestone says Gribkowsky was paid because he threatened that if he didn't get the money he would tip off the UK tax authority HM Revenue & Customs (HMRC) with the false allegation that the F1 boss controlled Bambino. It may sound particularly esoteric but in fact this was about the most severe allegation anyone could make against Ecclestone. There is a simple reason for this.

The Liechtenstein-based Bambino trust was established in December 1997 by Ecclestone's Croatian ex-wife Slavica who is one of its three beneficiaries along with their two daughters. Its key assets were shares in F.O.C.A. Administration, the UK company now known as Formula One Management (FOM), which directly held the rights to F1 and was previously wholly-owned by Ecclestone. He says he was advised to transfer his shares in it to Slavica because she had not lived in the UK long enough to be domiciled in the country. Accordingly, if he had died she would have had to pay 40% inheritance tax on money received from him even though spouses are usually exempt.

Ecclestone is 82 and during the late 1990s he suffered from heart problems which led to him having a triple bypass in 1999. This was the driving force behind the creation of the trust but it came with a catch. As a UK taxpayer, Ecclestone was not allowed control over the trust otherwise it could be declared a sham and tax would have to be paid on it. Essentially it could be considered tax evasion.

The reason for this lies in a clause in the Income and Corporation Taxes Act 1988, which has since been carried over to the Income Tax Act 2007. It states that if a UK resident transfers assets to a non-domicile and income becomes payable to the non-domicile, the transferor must not at any time have "the power to enjoy" that income otherwise it will be deemed to have been his own.

Accordingly, as it states in the prospectus for the planned stock market flotation of F1 "Mr Ecclestone is not an adviser to the trust and has no direct or indirect control or influence over Bambino, the trust, the trustees or the protectors of the trust, nor any directors or officers of any of those entities or any other entities controlled by the trust." So why did he pay Gribkowsky when he threatened to make the false tip-off?

In November 2011 Ecclestone testified as a witness in the trial against Gribkowsky and said that although it is not true that he controls Bambino, he was concerned HMRC might take the allegation seriously. If this had happened Ecclestone would have been liable to pay tax on the billions that the trust has received from selling its shares in FOM and the burden of proof would have been on him to prove that the authorities were wrong. Ecclestone says that he paid Gribkowsky to avoid this happening. However, ultimately it didn't entirely avoid HMRC's gaze.

Once Ecclestone's reason for paying Gribkowsky had got into the public domain it soon came to light that HMRC was looking into it. In November 2011, shadow attorney general, Emily Thornberry, said "this is something that needs to be looked into and I am writing to the Attorney General to ask him whether he has looked at the case."

The Attorney General's Office, which oversees the Serious Fraud Office, confirmed it would examine the issues raised by Thornberry and then in March 2012 Ecclestone was notified that HMRC was investigating his affairs. Sylt's report in the Telegraph reveals that there is no suspicion of tax evasion.

Buried deep in the 498-page float prospectus it states that "Mr Ecclestone was notified in March 2012 that HMRC in the UK is currently investigating his tax affairs focusing primarily on his connections directly and indirectly to offshore trusts. HMRC has informed Mr Ecclestone that the investigation is being conducted in accordance with Code of Practice 8. This is applied in cases where there is no suspicion of tax evasion, but instead HMRC wishes to investigate if any tax planning undertaken by a taxpayer is effective to achieve its intended effect. The purpose of the investigation is to identify if there are any amounts of underpaid tax."

It remains to be seen what will HMRC will conclude but, as with the investigation in Germany, it seems that the black clouds are behind Ecclestone.