Even with bought-and-paid-for Senators urging the FCC to hurry up its review of the pending merger of Comcast and Time Warner Cable, there is only so much the regulators can do when they don’t have the documents they need to complete that review. That’s why the FCC has once again hit the pause button on the time clock for this mega-merger.

In a letter [PDF] sent Monday by FCC Media Bureau Chief William Lake to executives at Comcast, TWC and Charter (which will get a few million new customers as part of the deal), the Commission explains that the 180-day review “shot clock” has been stopped until Jan. 12, 2015, because TWC has delayed handing over nearly 40,000 documents requested by the FCC.

According to the letter, the documents in question were supposed to be turned over in September but 7,000 were held back “based on an inappropriate claim of attorney-client privilege.” These were eventually turned over in early December.

However, there were another 31,000 additional documents that had not been provided due to “vendor error.” At first the Commission was told it would not receive these files until Dec. 30, but they apparently were delivered yesterday.

“The effect of these late disclosures has been to slow down the Commission’s review of the Comcast/TWC/Charter transaction,” reads the letter, “in particular because sections of the review that staff had thought were complete now must be reopened to take account of the additional documents that have been disclosed.”

The letter also chastises TWC for not taking the initiative to correct its filing goofs.

“While the Commission can understand and accept that minor errors can occur… it expects applicants to promptly correct errors, without prompting, when they occur,” writes Lake, who concludes that TWC’s failure to rectify its mistakes has “interfered with the Commission’s ability to conduct a prompt and thorough review of the pending applications.”

In a statement, TWC attempts to put the delayed 38,000 documents in perspective.

“We already have provided the FCC more than five million pages of documents and we will continue to provide the FCC everything that they need to review this transaction,” said the company.

Though the review clock is now delayed until mid-January, this does not delay today’s deadline for all parties with an interest in the merger to file their official responses to comments with the FCC. You can expect to hear later today from the “Stop Mega Comcast” coalition, which includes our colleagues at Consumers Union.

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