2018 Topps Baseball Forum

The home run challenge insert cards have a number on the back that looks like a serial number

See here: http://www.tradingcarddb.com/ViewCard.cfm/sid/167431/cid/10719879/2018-Topps---Home-Run-Challenge-HRC-WM-Wil-Myers?PageIndex=1

Does this count as a serial number? My guess is Topps numbered the cards so they could track each Home Run Challenge code to each specific card. 

Any print run is unknown at this point.  Should A) this be included in the note field and B)if so, how to note it?

These would be the same as any redemption card, as (I'm thinking) it's a code to be entered online, to register the card and pick the date you think the player will hit a home run. Looks like you win a prize if the player actually hits a home run on the date you supply. Simply like the codes on the old Attax cards and Power Players from a couple years back. No SN.

Sorry I should have clarified. It's the number to the right of the scratch off. For the card I linked it says 0080.

Like CAD said, probably some type of batch code. Or a verifying PIN.  Have you tried entering your code yet?

I did. Only the scratch off number was required. So it likely is just as batch number as pointed out

Typically it is a unique number per card so that if you damage the code on the scratch off somehow and call Topps, they can tell you what the code should be.  They go through a verification process to make sure you actually have the card before helping you out, but that's what it is for.