Fabulous, a U.S. corporation, sells all of its rights to a German patent to Erffurt A.G. ("Efurt"), a German corporation, for $1 million, payable in ten equal annual installments with interest at ten percent on the deferred payments. Title is passed to Erfurt in Germany. The patent had an original cost basis of $400,000 and had been subject to total amortization adjustments of $200,000, all of which had been deducted in calculating German-source taxable income. What is the source of the gross income realized? If the sales price is cast in the form of a "royalty" of five percent of the net sales by Erfurt of products incorporating the patented invention, what is the result? Supposed Fabulous sells its German trademark "Fabulair" and associated goodwill to Erfurt for $5 million payable in five equal annual installments with interest of ten percent on the deferred payments. What is the source of the income realized?