In April Massa signalled his intention to take legal action against the results of the 2008 F1 world championship, which he lost out to McLaren's Lewis Hamilton by a single point.
Massa acted on information from former F1 supremo Bernie Ecclestone, who suggested that knowledge of the controversial 2008 Singapore GP 'crashgate' was available early enough for action to be taken before the result of the championship was made final.
In March Ecclestone was quoted in an interview by F1-insider saying the result of the Singapore race, in which Nelson Piquet Jr deliberately crashed to helped Renault team-mate Fernando Alonso win, could have been thrown out, which would have swung the title race in favour of the Ferrari driver.
Instead, the controversy was only formally investigated the following year, meaning it was too late to go back and amend the race or championship result.
After assembling a legal team Massa has now sent a so-called Letter Before Claim to the FIA and FOM, which sets out the details of the case the Brazilian intends to pursue in court.
According to the document, which Autosport has had access to, Massa's defence alleges that the Brazilian was "the victim of a conspiracy", with the FIA and FOM deliberately failing to take action even after becoming aware of the case.
The letter, addressing F1 CEO Stefano Domenicali and FIA president Mohammed Ben Sulayem, alleges that the two bodies' "motive to avoid a scandal" has cost the now 42-year-old Brazilian tens of millions of euros in lost earnings and bonuses.
"Simply put, Mr Massa is the rightful 2008 Driver's Champion, and F1 and FIA deliberately ignored the misconduct that cheated him out of that title," states the letter.
"Mr Massa is unable to fully quantify his losses at this stage but estimates that they are likely to exceed tens of millions of Euros. This amount does not cover the serious moral and reputational losses suffered by Mr Massa."
The letter goes on to state that if there is no significant response within two weeks, the lawyers are instructed to start legal proceedings.
Intriguingly, Ecclestone has now said he could not remember giving the interview that led to Massa's legal campaign and added that he hasn't been approached by Massa or his legal team to verify his comments.
"I don't remember any of this, to be honest," the 92-year-old told Reuters. "I don't remember giving the interview for sure."
It remains to be seen whether or not Massa's team has a realistic avenue to challenge the 15-year-old championship result.
The FIA's International Sporting Code does not allow protests after a race and any right to request a review expires 14 calendar days after a competition – and four days prior to the date of that year's FIA prize-giving ceremony.
Furthermore, the FIA's judicial system is clear that the highest authority to make any ruling is the independent International Court of Appeal, and that any persons involved in a championship agree to abide by this.
In theory Massa could seek out the views of the Court of Arbitration for Sport (CAS), but it has no jurisdiction over the FIA on the matter.
The FIA statutes dictate that the CAS may only be involved in issues relating to the FIA's Anti-Doping Disciplinary Committee.
At the time of writing the FIA was unavailable for comment when approached by Autosport.
Additional reporting by Erick Gabriel
