unlimited...As I understand it, he was hired by Ian Telfer. To be clear, Watson has never claimed that he "invented" the streaming model, the attribute is mine. But I think the record is clear that he took the initial idea from Telfer and was the primary person responsible for refining it and putting it into practice at SLW. (Ideas are a dime a dozen, the genius is in actualizing them.)

From a 2010 interview with Watson:

MO:
How did you first get involved with Ian Telfer and Silver Wheaton?

Nolan Watson:
I was approached by Rohan Hazelton, a Harvard graduate and senior executive of Goldcorp (the world’s second largest gold mining company) and was told that at the age of 25 I was going to be given the chance to manage the finances for Silver Wheaton, which had 0 employees and a $300 million market capitalization. In addition, I would have the chance to work closely with Ian Telfer (who is now the Chairman of Goldcorp and Chairman of the World Gold Council). Obviously, the chance to work with someone of Mr. Telfer’s calibre was very appealing to me. Silver Wheaton was an idea for mine finance that had never been tried before and as the first employee I was able to use my entrepreneurial skills and build something tangible out of great idea.

MO:
Can you tell us more about your role at Silver Wheaton, how did you contribute to the company’s dramatic success in such a short timeframe?

Nolan Watson:
The streaming finance business model was new to the mining sector with Silver Wheaton so the main challenges were to sell companies on the benefits of silver streaming and to raise the money necessary to complete the streaming deals. While I was at Silver Wheaton I raised over $1 billion in debt and equity financing to grow the company. As the Chief Financial Officer, I also had approximately 60% of the companies employees reporting either directly or indirectly to me.

http://www.mo.com/nolan-watson-sandstorm/