Direct from the rules posted in the forums, the relevant section is in bold and red:
Trading
To perform a trade, always prefer to use the Trade Window over dropping the items unless you encounter an error, in such a case remake your lobby and report the error to the staff.
If you decide to not use the trade window, in the event of an error of any kind, we might not offer support to recover your items. You are forbidden of trading your PSOBB items for any 3rd party products or services not mentioned in these Terms except in an exceptional case approved by the staff, such cases are not general and only apply to the situation they were discussed and approved.
You are allowed to trade your PSOBB items for items in another game or a platform (market) like Steam however we do not encourage nor support it. We cannot undo trades involving 3rd parties and we won't restore items lost during such trades. You are not allowed to trade items for currency in other games that is explicitly bought with real money, this includes steam funds, and anything similar in other games or platforms.
You are not allowed to trade your PSOBB items for gift cards of any type like steam, skype, etc.
If you fail to follow these rules we might take action against your account, this applies to the players on both sides of the trade.
Locking this topic.