"It is the equivalent of going into libraries and burning books you don't like," Mail Online publisher Martin Clarke said.
BBC Economics Editor Robert Peston said Wednesday the removal of his 2007 blog post, which was critical of Merrill Lynch's then-CEO Stan O'Neal, means "to all intents and purposes the article has been removed from the public record, given that Google is the route to information and stories for most people."
Google has a market share of 90 percent in Europe's search market.
The company says it has already received more than 50,000 removal requests and its experts are going through them. The company is not saying how many appear to fall into areas the court specified as potentially objectionable: results that are "inadequate, irrelevant or no longer relevant."
Google is only starting to implement the ruling, and several German media contacted Thursday said they had not yet received notifications on articles scrubbed from search results.
The company from Mountain View, California, finds itself in an uncomfortable position. It has no choice but to comply with the ruling by the EU top court, which cannot be appealed, but many decisions to remove search results are likely to draw criticism.
"This is a new and evolving process for us," Google spokesman Al Verney said Thursday. "We'll continue to listen to feedback and will also work with data protection authorities and others as we comply with the ruling."
Proponents of the court decision say it gives individuals the possibility to restore their reputation by deleting references to old debts, past arrests and other unflattering episodes. They also note that the court specified Google should not remove links to information when the public's right to know about it outweighs an individual's right to privacy — for example when a politician or public figure seeks to clean online records.
The purge of search results will apply to Google's local search pages covering the EU's 28 member nations and four other European countries, encompassing more than 500 million people. Users in Europe who switch to the firm's American domain, Google.com, will find unaltered search results.
Moreover, Google is only deleting information that appears on its own results pages. It has no control over information on external websites, which did not fall under the court's ruling.