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Advertising expenses. You can deduct reasonable advertising expenses if they relate to your business activities.
Generally, you cannot deduct the cost of advertising to influence legislation. See Lobbying Expenses below.

You can usually deduct as a business expense the cost of public service advertising to keep your name before the public
if it relates to business you reasonably expect to gain in the future. For example, the cost of advertising that encourages
people to contribute to the Red Cross, to buy U.S. Saving Bonds, or to participate in similar causes is usually
deductible.

Foreign expenses. You cannot deduct the costs of advertising on foreign radio and television (including cable) where
the advertising is primarily for a market in the United States. However, this rule only applies to advertising expenses in
countries that deny a deduction for advertising on a United States broadcast primarily for that country's market.