Officials have refused to reveal details about more than 50 MPs renting second homes using taxpayers' money.
The expenses watchdog released a list of 269 MPs who rent homes at public expense and included information about their landlords.
But details about 51 of the 320 MPs who claim rental expenses were not included after complaints that to publish their landlord's name would be a security risk.
They were removed by the Independent Parliamentary Standards Authority (Ipsa) where an MP or landlord had shown the information could lead to their address being identified.
The redaction is reminiscent of attempts to hide the worst excesses of the expenses scandal, when documents were widely censored.
Providing the details would have exposed the full extent to which MPs are taking advantage of a loophole in new expenses rules that allow them to rent to each other.
In the wake of the 2009 scandal, rules were tightened that prevent politicians from claiming mortgage interest but they can still claim up to £20,000-a-year for renting a flat.
This means MPs can rent out their London properties and pocket the profits while using their expenses to fund rent on another property.
Although the practice does not break any rules, it fuels concerns that politicians are still able to profit from their Commons allowances.
The list was not published in full after Commons Speaker John Bercow intervened to highlight MPs' "grave" concerns about privacy.
An Ipsa spokesman said 85% of MPs had their landlords named, but added: "We need to consider in each case whether there are any security issues. We take that as seriously as we can."
Nick Clegg's landlord was one of those not disclosed for security reasons. A spokesman for the Deputy Prime Minister said: "This decision was taken on advice from the police."
The publication did reveal that Labour MP Jessica Morden rents from her colleague Madeleine Moon and Conservative Keith Simpson rents from Lord Flight.
The Sun newspaper also claimed that Tory MP Peter Luff rents a flat from Chelsea footballer Frank Lampard, while renting out his own London home.
A spokesman for Lampard said the star did not know who his tenant was because it was let through a management company.
Mr Luff's representative said he had no idea if he was renting from Lampard or not.
Equalities Minister Helen Grant has also defended her claim for the maximum in expenses to cover accommodation in London despite living just 19 miles from the Commons.
Mrs Grant lives in a £1.8m home in Reigate, Surrey - outside her Maidstone constituency - and also rents a Thameside flat near the MI6 building in Vauxhall, funded by the taxpayer.
The Conservative minister is eligible for a second home allowance on parliamentary expenses because her constituency is outside London.
The expense claims were uncovered in an investigation by Channel 4's Dispatches.
A spokesman for Mrs Grant said: "Mrs Grant's constituency has been deemed by Ipsa to be a non-London constituency and she is therefore fully entitled to use her rental accommodation allowance either in London or in the constituency.
"She has a base in her constituency at her mother's property, where her son also lives, so she sees no need to rent a further property there.
"The focus of her time and responsibility has always been Maidstone and the Weald."
Mrs Grant's London flat is supported by expense claims of £1,666.67 per month - the maximum allowed within the rules. She has filed claims for rent since March this year.