Permanent establishment profit attribution: only profits attributable to a PE may be taxed by the other Contracting State. Business profits are taxable only in the residence State unless business is carried on in the other State through a permanent establishment; then only profits attributable to that PE may be taxed there. Profits attributable to a PE are those it would earn as a distinct and separate enterprise under similar conditions. Deductions for PE expenses are permitted under the taxing State's law, but amounts between PE and enterprise for royalties, fees, commissions, management services or (except banking) interest are disregarded. Customary apportionment may be used if consistent with these principles; purchases alone do not attract profits.