隨著網際網路技術與數位載體的發展，進入數位化時代著作不再只限實體著作物形式進行交付，而能以數位化格式透過無遠弗屆的網際網路傳輸。事實上，線上交易著作權商品已成為民眾日常生活中不可或缺的活動。然而無論是線上購買實體著作權商品，例如紙本書、音樂CD、影音DVD，或是線上交易後直接下載電腦軟體、數位音樂，或是電子書等數位著作權商品於個人行動裝置，民眾逐漸發現無法比照以往購買紙本書、音樂CD、影音DVD 等實體著作權商品一樣，透過二手市場轉售，以填補購入新品的支出，原因在於著作權人將著作權商品之交易契約定性為「授權使用契約」，並附加限制轉讓或使用條款。此類情況在數位著作權商品交易市場儼然已成常態，著作權人據此主張持有數位著作權商品者是「被授權人」而非「所有權人」，因此不適用散布權耗盡規定而無權轉售、散布。民眾因締約弱勢與使用需求而只能被迫接受授權契約限制條款，失去自主決定權能，著作權人利用授權契約規避散布權耗盡規定之適用，從而打壓著作權商品二手市場，不僅形同實質上以私法契約凌駕著作權限制規定，同時也阻礙二手商品與新品競爭，如同變相限制競爭。長遠以觀，著作權制度藉由散布權耗盡規定竭力維持之著作權人和著作權商品所有權人之間的權利平衡勢必改變，甚而危及財產轉讓自由。所以筆者擬以與本議題相關的美國案例為主軸，論析法院之判決理由，並介紹美國學界對本議題之見解，最終提出筆者之意見，以期藉此提醒學術界和實務界關注授權契約限制條款引發之著作權問題。

With the advancement of Internet technology and digital media, copyrighted works in the digital era are no longer delivered only in the material object forms but are transmitted in digital forms through the far-reaching Internet. In fact, online trading of copyrighted goods has become an integral part of people's daily activities. Either online purchasing of copyrighted goods, such as books, music CD, video DVD, or online trading and downloading of computer software, digital music, e-books to personal mobile devices, consumers gradually realize they are unable to resell their copyrighted goods through second-hand market because copyright owners specify their trading transactions as licensing and impose consumers additional restrictions on transfer or use of copyrighted goods. Various kinds of restrictive licensing has become the norm in the digital era, whereby copyright owners argue that the holders of digital copyrighted goods are licensees rather than property owners, and therefore consumers cannot invoke the first sale doctrine to defeat the copyright infringement claims. Consumers are compelled to accept the restrictive licensing, losing authority to alienate copyrighted goods they possess. Copyright owners use the restrictive licensing to circumvent application of the first sale doctrine and undermine the second-hand market for copyrighted goods. The actions taking by copyright owners not only tantamount to override copyright restrictions by private contracts, but also hinder the second-hand market for copyrighted goods and restrict competition. In the long run, the first sale doctrine of the copyright system striving to maintain the balance of rights of copyright owners and consumers is bound to change and can even undermine the freedom of alienation of property. As a result, this article is intended to address relevant U.S. cases and discuss copyright infringement and first sale issues caused by the restrictive licensing.