brief history - I think Sony licensed the Izotope "mastering" plugins back when Sound Forge 9 was released. At that time the plugins were licensed for use with Sound Forge only. Except that the first customers to purchase Sound Forge 9 received a version of the plugin installer that did NOT lock the plugins to Sound Forge. Lucky few!
 
Since then the plugins are locked. On the good side this was my introduction to Izotope plugins. (Previously I had been so annoyed with their marketing that I never gave the plugins a listen.) And the plugins are magnificent!!! So I ended up  purchasing RX, and one of these days I will purchase Ozone. (For now I am happy using the SF plugins<G>!)

I suspect it's locked - I also have SF 11 and have never been able to pick those Izotope plugs up. Sony/Magix have become the biggest a**holes in the software universe IMO. They deleted all the Noise Reduction 02 (which is NOT locked and worked great with SPLAT) serial numbers out of my account during the transfer and I can't get anyone to answer an email, let alone pick up a phone.

Confirmed - they are locked. I went the izotope support route years ago and they let me know that the suite was on contract with Sony.
That suite was unavailable separately from iZotope.

Like someone else mentioned, it was the gateway drug to other offerings from iZotope.
I highly recommend checking out Ozone or Ozone Advanced, which is far better than that stripped-down "mastering" suite.
(The stand-alone version of Ozone is nice, runs plugins, and is worth the cost of admission. If you can step up to the advanced during a sale it makes it all the better, as then all the modules can be used individually in Sonar.)

And yes - too bad Sony did not know what to do with Sound Forge and sold it to a junk software company that has no clue.

SF 11Pro is still integrated in my Utilities menu in SPLAT, as is iZotope's RX4 Advanced.

RX will continue it's integration, but I'm afraid the same cannot be said of Sound Forge.

Quite a shame.

thanks everyone for the great info - very informative and all makes sense. I had SF9 and used it some, but it was out to pasture until I got an upgrade offer for Vegas 14 suite (I was still on vegas 11) with SF11 for a great price so I figured I grab it. Definitely have been mulling getting Ozone for some time now - this will probably cost me in the long run :)

MAGIX has been a total pain in the butt for me too in terms of getting support on Sony products.  Their on-line and off-line authorization sucks. It took over a month for them to allow me to re-authorize CD Architect 5.2 to run on the same DAW I had used it on for years (after cloning my OS to an SSD).  I know, that is an old low-end product but I bought it with both Soundforge Pro 9 and 11 and I want to use it!
 
And, yes, I have never been able to get the Mastering Bundle to work anywhere but in SoundForge.  Its odd that Nectar Elements is unlocked and can be used in Sonar.

Wow good to know that the vendors can lock us out.
 
I will be more careful now.
 

The Eula for the sound forge iZotope bundle explains that it is locked to SF. These things are common and are based on licensing arrangements so a vendor can get access to extra value products to bundle up with their own.

I utilize Sound Forge and just additional confirmation they are locked out to Sonar.