Using MS-PL licensed library for internal company use

Question

I want to use a MS-PL licensed library in a proprietary software, but it'll run inside my company, with no external distribution.

Does the license allows this kind of usage or it constitutes a violation of the license?

Answer 1

From MS-PL:

1. Definitions

The terms "reproduce," "reproduction," "derivative works," and "distribution" have the same meaning here as under U.S. copyright law.

This then directly goes to the copyright law. From bitlaw:

The distribution right grants to the copyright holder the exclusive right to make a work available to the public by sale, rental, lease, or lending.

Or the more wordy text Title 17 USC § 106 (3)

Subject to sections 107 through 122, the owner of copyright under this title has the exclusive rights to do and to authorize any of the following:

...

(3) to distribute copies or phono records of the copyrighted work to the public by sale or other transfer of ownership, or by rental, lease, or lending;

Again, note the 'to the public' in there.

As described in the original poster's question:

but it'll run inside my company, with no external distribution.

This is not to the public and does not constitute distribution of the work.

That said, I am not a lawyer, and thus if you have specific issue with this you had best contact your company lawyer to get an authoritative answer.