These expenses include unreimbursed employee business expenses, expenses for the production of income, tax - return preparation expenses, and many others too numerous to mention here. (fool.com)
In most cases, you can deduct these other taxes only if they are expenses incurred in a trade or business or in the production of income. (money.stackexchange.com)
The term trade or business generally includes any activity carried on for the production of income from selling goods or performing services. (law.stackexchange.com)