The OFT will determine whether "individual restrictions are anti-competitive", a spokes-man said yesterday.
The contracts guarantee the two cable companies long-term supply of Sky pay-television programming in exchange for their agreement not to compete with BSkyB on film or sport programming.
Several cable companies, including Videotron and International CableTel, had complained to the OFT that the contracts constituted restraint of trade. Other cable companies felt under pressure to sign similar contracts to secure popular programming controlled by BSkyB, 40 per cent owned by Rupert Murdoch's News Corporation. International CableTel has complained that the amount it would pay to BSkyB for programming would increase by as much as 20 per cent if it did not sign a supply agreement.
"There have been representations from other cable companies," the OFT spokesman confirmed, saying that the office would take several days to review the contracts, which were yesterday placed on the public register. The spokesman would not confirm suggestions that other media companies had also lodged protests.
If the non-competition clauses are deemed "significantly" restrictive, the OFT would refer the matter to the Restrictive Practices Court for adjudication. The office could also reach an informal agreement with the signatories to revise the disputed clauses.
They have until 30 June to reach a supply agreement, under terms established by the OFT.