I think it's the other way around. The BBC public radio are (were?) not allowed to condone -any- private businesses or products. Then it get's a bit tricky. Tr

I think it's the other way around. The BBC public radio are (were?) not allowed to condone -any- private businesses or products. Then it get's a bit tricky. Trademarks are a consumer protection device which affords the consumer to differentiate between competing products. As the song appeals to a chewing gum, and it's assumed that the general public are aware of one brand, two brands or 50 brands of spearmint-flavoured chewing gums for purchase - the radio may reason that the lyric would be unfit according to their mission. It's less about any actual trademark such as a Spearmint® Chewing Gum, than it is a public association to some marketed goods (and the BBC's stated mission to not condone such). This is just a random reasoning of mine, so a grain of salt etc. This entry mentions this: https://en.wikipedia.org/wiki/Does_Your_Chewing_Gum_Lose_Its_Flavour_(On_the_Bedpost_Overnight%3F) https://en.wikipedia.org/wiki/Does_Your_Chewing_Gum_Lose_Its..., but the issue is marked 'dubious'.