No, that's not true. It just shows bad faith on the part of the chef. I believe the chef worked for the restaurant, and any output of his would be done under the auspices of the restaurant. Fact is, he didn't pay for it, he didn't typeset it, he didn't send it to the printer, he didnt... you get the picture.
This chef has an ego problem. Menus change with the seasons and if you're confident enough in your abilities then who cares. You just keep working on stuff. There aren't any secrets. What a lamer.
First of all, just because something is published doesn't mean it's copywrited.
And what does he mean by publishing, running off a few copies at Kinkos?
Nothing says that a restaurant owner or chef can't take a recipe that's been published in a book (copywrited) and use it to serve his/her guests. As a matter of fact, it happens all the time.
Besides, a menu is just a list of dishes offered, not the great American novel.
I've never heard of any plagiarism suit contesting a menu. The notion is so ridiculous, it'd be thrown out in a NY minute.
Technically, if you're the creator of the work, then you own the copyright. You don't have to register anything. All you have to do is show that it's your work. Most of the time that means attaching your name to the work, like the use of a c in a circle, followed by the date and the name of the creator. That's all it takes.