From an article in The Economist:
For his part, Mr Putin appears, at least for now, to have ruled out a full-frontal invasion. On June 24th he theatrically instructed the ever-loyal upper house of parliament to cancel the authorisation for military force in Ukraine that he had ordered up in early March. The move was largely an empty fob to Mr Poroshenko and another way to ward off more Western sanctions.
What does the expression an empty fob to smb. mean here?
An empty (futile, obvious) fraud attempt, possibly? Or something more imaginative, like Mr. Poroshenko suddenly finding his watch pocket (fob) empty?
I find instances of the former sense in oldish texts (like this one, from the XIX century)
One has got a broken nob
The other's got an empty fob