proprietary platform

Yahoo! Application Platform Terms of Use : « ...

• If You use of Yahoo! APIs to build your YAP Application, you agree to the Yahoo! API Terms of Use http://info.yahoo.com/legal/us/yahoo/api/api-2140.html...
• If Your Application allows Users to download, view, listen to or otherwise access or distribute third party content provided by other Users, you must post and implement a copyright policy that complies with the Digital Millennium Copyright Act (“DMCA”), which must include, without limitation:...
• By submitting Your Application, You warrant, represent and covenant that: 1. You own or have the necessary licenses, rights, consents and permissions to all patent, trademark, trade secret, copyright or other proprietary rights (“Rights”) to Your Application and any other works that You incorporate into Your Application to submit your Application to Yahoo! for distribution consistent with the YAP, and You authorize and license Yahoo! and its affiliates to use Your Application and any other works that You incorporate into Your Application in the manner contemplated in these YAP Developer Terms.

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Yahoo! APIs Terms of Use (Yahoo Developer Network Terms of Use): « ...

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  The Yahoo! APIs are owned by Yahoo! and are licensed to you on a worldwide (except as limited below), non-exclusive, non-sublicenseable, revocable basis on the terms and conditions set forth herein. These Terms of Use define legal use of the Yahoo! APIs, all updates, revisions, substitutions, and any copies of the Yahoo! APIs made by or for you. All rights not expressly granted to you are reserved by Yahoo!.

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Yahoo! Social Directory: "...Use of the Yahoo! Social Directory API is governed by the Yahoo! APIs Terms of Use...

Yahoo! Contacts API: "...Use of the Yahoo! Contacts API is governed by the Yahoo! APIs Terms of Use....

Yahoo! Status API: "...Use of the Yahoo! Status API is governed by the Yahoo! APIs Terms of Use.....

Yahoo! Updates API: "...Use of the Yahoo! Updates API is governed by the Yahoo! APIs Terms of Use....

it's enough for me; sorry, i can't go further...