Sept 12 (Reuters) - The US Federal Trade Commission is

investigating whether Amazon.com ( AMZN ) and Alphabet's

Google misled advertisers that place ads on their

websites, a source familiar with the matter said on Friday.

The investigations are being conducted by the FTC's consumer

protection unit, and focus on whether Amazon ( AMZN ) and Alphabet

properly disclosed terms and pricing for ads.

Alphabet and Amazon ( AMZN ) did not immediately respond to Reuters

requests' for comments.

The agency is seeking details about Amazon's ( AMZN ) advertising

auctions and whether it disclosed "reserve pricing" for some

search ads, according to the source. Reserve pricing refers to

the minimum price advertisers must accept before they can buy an

ad.

The FTC is also examining Google's practices, including

its internal pricing process and whether it increased the cost

of ads in ways that were not disclosed to advertisers, the

source said.

Bloomberg News first reported the development.

(Reporting by Deborah Sophia in Bengaluru and Jody Godoy in New

York; Editing by Mrigank Dhaniwala and Shinjini Ganguli)