Yahoo files e-book advert system patent applications
Yahoo has signalled it is investigating e-book adverts as a way to stimulate its earnings.
It says in two US patent applications that ads for digital book readers have been "less than optimal" to date.
The filings suggest that users could be offered titles at a variety of prices depending on the ads' prominence
They add that the products shown could be determined by the type of book being read, or even the contents of a specific chapter, phrase or word.
The paperwork was published by the US Patent and Trademark Office late last week and relates to work carried out at the firm's headquarters in Sunnyvale, California.
"Greater levels of advertising, which may be more valuable to an advertiser and potentially more distracting to an e-book reader, may warrant higher discounts," it states.
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