Google on Thursday began censoring search tools to prevent piracy, as first announced in a policy shift last December.

The change affects Google's Autocomplete and Instant tools—the services that predict your results before you finish typing—not its search results. Basically many terms with the word "torrent" in them have been filtered out of Autocomplete, along with other terms related to downloading services. Examples include BitTorrent, torrent, utorrent, RapidShare, and Megaupload, according to numerous reports on Thursday morning.

PCMag tested searching for some of the terms listed above in multiple browsers and came up with different results. On Google Chrome, a search for "BitTorrent" draws up a couple of auto-suggestions, but also displays a new "remove" button next to each result where you can remove the auto-suggestion altogether (this option didn't exist for any other terms we tried). On Microsoft Internet Explorer and Apple Safari, the Autocomplete function is indeed missing for items like BitTorrent, RapidShare and uTorrent.

Simon Morris, BitTorrent VP of product management, told TorrentFreak, "We respect Google's right to determine algorithms to deliver appropriate search results to user requests. That being said, our company's trademarked name is fairly unique, and we're pretty confident that anyone typing the first six or seven letters deserves the same easy access to results as with any other company search."

Last December, Google pre-empted four changes to its copyright infringement-prevention policy: first, to act on copyright takedown requests within 24 hours; second, to simplify the process for takedown requests; third, to improve its AdSense anti-piracy review; and fourth, to prevent terms "closely associated with piracy" from appearing on AutoComplete.

Google declined to comment, but pointed to its December blog post where it talked about making the changes over the next several months.