Does Pantone define a tolerance for reproduction of PANTONE colors?
Pantone does not set tolerance levels for reproduction of PANTONE colors by commercial printers.
There are many variables that will effect final printed results. Some of these variables are indicated in the copy pages of the PANTONE guides. In many cases, organizations or large corporations will establish Light/Standard/Dark tolerance levels which are used as a QC benchmark for incoming materials.
Please keep in mind that Pantone, Inc. does not manufacture ink and all ink that is labled as a PANTONE Color is supplied by a licensed ink vendor and/or manufacturer.