Canon General / Re: Canon Issues Product Advisory For the EF300mm f/2.8L IS II USM, EF400mm f/2.8L IS II USM, EF500m« Last post by neuroanatomist on September 18, 2014, 11:24:57 PM »
To date, Canon has issued only 5 lens firmware updates. Four of them are covered by this advisory, the other I referred to above, which was available for download and application via camera body.
There was the 200/2 IS issue ith the 5d3, among other teles.
Was the fix for that issue a lens firmware update? The Canon service advisory mentions only 'repair'.