Only if you are going to conform to the latest standard. You can still use ANSI Y14.5M-1982 or Y14.5M-1994. The important thing is that you conform to whatever standard, and your suppliers do the same.
"Art without engineering is dreaming; Engineering without art is calculating."
Have you read faq731-376 to make the best use of these Forums?
Nobody has complained yet about referencing a superseeded specification. Is it wise to leave a superseeded spec on your drawings? or is it better to keep up and start changing over to the new spec? I know they are not identical, but I have to think they are pretty close.
Things change with the new spec, especially between the 82 version and the 95 version where some symbology and whether or not it's MMC by default etc. changed.
DO NOT just change the spec called up on the drawing without updating the drawing to address the other changes.
It's is perfectly legitimate for old drawings to still call up the old spec.
Eventually it can become problematic because finding vendors that actually know the differences/the old spec can be tricky - but it's not fundamentally illegal or something.
It may be a good idea to create new drawings to a newer version of the spec though. Even here though the choice isn't immediately clear. The 2009 standard really came out at the beginning of 2010 and a lot of people aren't up to speed on it yet, so short term using the 95 standard may be easier. However, long term you'll hit the problem you have now sooner.