Positive and negative of COMPETITOR BRAND BIDDING IN PPC

REASONS TO AVOID BIDDING ON YOUR COMPETITORS BRAND TERMS

It can annoy your competitors, and you’re likely to receive a cross email/call asking you to stop. It is however completely legal, and does not break any of Google’s policies as long as you are not ‘passing off’ or using trademarked terms in your ad text.
It doesn’t always work – especially if your product has significant differences, has a higher price, or where brand loyalty is high.
It can result in high bounce rates – especially if your adverts suggest you are the competitor that you’re bidding on (something to avoid). You need to work your adverts and landing pages hard to ensure you are giving the user a good experience.
If your competitors notice it – they can also retaliate and start bidding on your brand.

You’re targeting people who have a specific interest in buying relevant products/services.
Total cost, cost per click and subsequent cost per conversion is normally very low.
You can achieve a good ROI with a small investment. This depends on the scale, volume and relevancy of the competitors.
It can be good if your brand is not yet established. You can ride on the back of a competitors marketing activity/brand.
You can exclude the area where you know their head office is to reduce the chances of your competitors noticing.