Great question, I appreciate it. It seems I don’t think I have a definite, crystal-clear answer to it yet though.

When asked regarding stipulations for Minor League Rule 5 selections on Twitter, MLB.com Jays reporter Gregor Chisholm wrote:

No stipulation. The players can be put at any particular level without the risk of losing them.

Baseball America also had an article on the Rule 5 Draft and here’s what they had to say:

There are Triple-A and Double-A segments of the Rule 5 draft, with price tags of $12,000 and $4,000 respectively. Minor league players not protected on the reserve lists at the Double-A and Class A levels are subject to selection, but almost no future big leaguers emerge from this process. It’s basically a tool for major league teams to fill out affiliates rather than obtain talent.

I have a feeling that prospects can be assigned to any Minor League affiliate, or at least the same level.

In 2005, Eugenio Velez was claimed by the Giants from the Blue Jays in the Minor League portion of the Rule 5 Draft. Velez played for Class-A Lansing that season in the Jays’ system, and in 2006 in the Giants’ system he played for Class-A Augusta.

It also seems highly unlikely that the Jays would bother selecting these two players if they had to forcefully bump one from Double-A to Triple-A, and the other from the lowest level of rookie ball straight to Double-A, skipping three Minor League levels.

The only location that I could find the information you stated above was on Wikipedia, where they do not give a source for it anywhere. From Wikipedia:

Organizations may also draft players from AA or lower to play for their AAA affiliates (for $12,000) and may draft players from A teams or lower to play for their AA affiliates (for $4,000).

Hopefully this all helps, and I’ll continue to try and find a definite answer.

-JM