Microsoft and Google have joined the opposition to a bid by the US hotel industry for permission to block guests from using personal wi-fi hotspots.
Earlier this year the the Federal Communications Commission hit Marriott a $600,000 fine for using network gear to blind guests' devices to any hotspot other than its own wi-fi network.
Responding to a complaint about the practice from 2013, the FCC said the practice violated the individuals right to use their own connections, which business travellers - particularly attending large conferences - know can be faster and more reliable than the hotel's own network.
Marriott argued it was protecting guests from "rogue wireless hotspots" and in August, Marriott, the American Hotel & Lodging Association and others petitioned the FCC for a declaratory ruling on the matter.
The group highlighted that its petition was not seeking ruling on the use of signal jammers, which was clearly not permitted by the FCC's rules, but the right to provide a secure and reliable wi-fi service to guests on their premises.
But Microsoft has now weighed in against the hotels' petition, noting that while it didn't involve jammers, it was "irrelevant" since the Commissioner considered jammers to "be a broader range of devices 'that are deigned to block, jam, or otherwise interfere with authorized radio communications."
Google also opposed the petition in its own filing. "While Google recognizes the importance of leaving operators flexibility to manage their own networks, this does not include intentionally blocking access to other Commission-authorized networks, particularly where the purpose or effect of that interference is to drive traffic to the interfering operator's own network (often for a fee)," it said.
The period for public comment closed last Friday: the FCC must now make a decision whether to accept or reject the petitioners' request.