Starting in the 1980s, the USPS started adding special service inscriptions on certain stamps. Take Scott #2258 for example. In red ink, itís marked ďPre-sorted First ClassĒ. Many, but not all, of these issues are fractional coil stamps issued to meet a special mailing rate such as bulk rate, presorted, or non-profit. In later issues, the service inscription was part of the stamp design, such as Scott #3207. The USPS refers to these issues as Service Inscribed stamps because they designate the type of mail they are designed for.
A few stamps like Scott #2127 come both ways. There is a standard version of the stamp with no inscription. There is also a version that has a service inscription printed on the stamp, in this case in black ink.
Large mailing firms like these stamps because itís a stamp on a letter. The recipient is more likely to open an envelope with a stamp on it than a permit imprint. If it has a stamp, it must be important. Many of these mailings are for non-profit or political groups seeking donations.
A customer recently ordered used copies of some of these service inscribed stamps. He returned them because they didnít have any cancellation on them. He thought I was sending mint stamps instead. Because he collected used US issues, he wanted copies with cancels. I explained the situation.
Used copies of service inscribed stamps almost never have a cancel. Mint copies have gum. Used copies do not have gum. Why?
Service inscribed stamps are used on classes of mail that normally do not go through the cancelling machine. Hence, no cancel on the stamp.
You can use service inscribed stamps on first class mail as long as you have a permit at the post office. In these cases, service inscribed stamps may receive a cancellation.
If you collect used US issues, itís perfectly acceptable to collect service inscribed stamps with no gum and no cancellation. That is the norm for these issues.