Google has felt the need to defend the way it does business as it faces opposition for a number of recent moves.
This week, Microsoft joined Fairsearch.org, an organisation comprised of various online firms that oppose Google's acquisition of travel software provider ITA.
The central cause of concern for Microsoft and Fairsearch.org is ITA Software powers many travel search rivals. If Google gains control over that software then the search giant could dominate the online air travel market, the Redmond firm and its new allies have argued.
Google is also facing an antitrust investigation from the European Commission.
The search firm has been accused of having "abused a dominant position in online search" by lowering the ranking of unpaid search results of competitors who offer very targeted services in order to give Google's own services higher prominence.
In a blog post, Google deputy general counsel Don Harrison responded to a Washington Post article about the company's acquisitions and antitrust law.
"Antitrust law is designed to protect consumers, not competitors, and our acquisitions have created great things for consumers," Harrison wrote.
"For startups, getting acquired is often the path to success (especially given the difficult IPO market), so stopping large companies from making acquisitions would only deprive startups of another potential bidder and investors of a potential return on their invested capital. You can't be both pro-economic growth and anti-acquisitions."
Harrison said antitrust laws adequately protect competition and consumers' interests.
"Most observers would agree that the antitrust laws are pretty durable and the courts have done a good job applying the law to new products and technologies," he added.
"For our part, we'll continue to make sure that our business practices reflect our commitment to compete fair and square."
