Olympus registered the 300mm f/4.0 ZUIKO PRO lens at Novacert in Russia. This means the announcement will happen within the next 2-3 months.

via Digicameinfo.

Back in June (article here) I told you that Olympus delayed the 300mm PRO f/4.0 Zuiko lens launch to add in lens image stabilization. And today Digicameinfo confirmed the lens has in body stabilization.

My source also explained why Olympus decided so:

Olympus considers to make the new 300mm f/4 PRO lens with OIS, to complement IBIS in Olympus bodies (which is less effective at really long focal lengths) and also be attractive for Panasonic users.
I know, it is the first for Olympus, but then it is going to be very specialized, and they have decided than without Panasonic user market it would not have enough sales to pay to its development, and that was the cause of its delay.
Lens construction is 17 elements in 10 groups, 2 SuperED elements, internal focusing.

Other sources told me the lens will ship in early Spring 2016.

Reminder: The 300mm PRO lens is listed here:
Olympus M.ZUIKO DIGITAL ED 300mm f/4 PRO Lens (here at BHphoto).

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