數位產業在蓬勃發展的同時，盜版的問題也更容易存在，其使用成本低且便利性高，十分容易成為消費者的最終選擇，這將對正版商造成巨大衝擊，正版商可能削價競爭而導致獲利降低，也有可能降低其投資更新產品或服務的意願，而數位產品產業中，以基本軟體為基礎，進一步提供附加產品或服務的銷售模式已經越來越普遍，盜版的存在將可能對此種銷售模式的廠商威脅更甚，廠商如何因應及抑制盜版已是刻不容緩的問題，故本研究依據策略重心的不同，討論正版廠商可能會朝兩種不同的方向去抑制盜版：(1) 提高消費者使用盜版成本的阻撓策略，例如：提高執法力度、設計防盜機制等，(2) 改變商業模式，提高消費者使用正版動機的免費增值策略。然而有些說法指出，盜版也許可以為正版增加曝光度及口碑，為正版帶來正向的網路效應，或是經過成本與收益的權衡，有時候放任盜版，採取不約束策略也許對正版廠商更有利可圖。故本研究透過量化的解析模型探討同時提供基本與附加產品或服務之正版商以獲利最大化為目標，面對盜版應該採取不約束、阻撓或是免費增值策略，並進一步延伸將網路效應納入模型中討論。本研究發現，不存在網路效應時，當盜版使用成本高，正版廠商應該採取不約束策略以最大化其獲利，在盜版使用成本偏低時，免費增值策略將有利可圖，而在盜版使用成本偏高或偏低時，阻撓策略將會是最劣勢策略。而本研究以同產品跨版本網路效應 (盜版產品為正版產品帶來之網路效應) 為基礎，依據產品類別 (基本、附加) 及產品版本 (正版、盜版) 延伸出三種不同的網路效應組合，結果發現無論何種網路效應存在都將提高正版廠商之總獲利，不同的網路效應組合作用下，對基本與附加產品的邊際利潤、需求將產生不同的影響，而只有跨產品同版本的網路效應存在時，正版廠商才能做到同時兼顧正版需求及獲利最大化。

The low cost and convenience of piracy makes it the ultimate choice of consumers. This will have a huge impact on the originals, who may cut prices and reduce profits, and may be less willing to invest in new products or services. In the digital product industry, the sales mode of providing add-on products or services based on the basic products is becoming more and more common, and the existence of piracy may pose an even greater threat to firms in this sales pattern. Therefore, this study discusses the two different directions that originals may take to curb piracy, depending on the focus of their strategies: (1) deterrent strategies that increase the cost of piracy to consumers, such as increasing law enforcement and designing anti-piracy mechanisms, and (2) freemium strategies that change business mode to increase consumers' motivation to use original copies. However, some argue that piracy may increase the exposure and reputation of the original version, bringing positive network effects to the original versions, or that, after weighing the costs and benefits, it may sometimes be more profitable for the originals to let piracy go and adopt a non-action strategy (Take no action against piracy). Therefore, this study uses a quantitative analytical model to investigate whether originals who provide both base and add-on products or services should adopt a no-action, deterrence, or freemium strategy in the face of piracy in order to maximize profits. This study found in the no network effect scenario, when the cost of piracy is high, originals should adopt a no-action strategy to maximize their profits. When the cost of piracy is low, the freemium strategy will be profitable. When the cost of use piracy is high or low, the deterrence strategy will be the most disadvantaged strategy. This study is based on the cross-version network effect of the same product (the network effect from piracy to original) and extends three different networks according to product categories (base, add-on) and product versions (original, pirated). The results show that no matter what kind of network effect exists, it will increase the total profit of originals. Under different network effect combinations, the marginal profit and demand of base and add-on products will have different effects, and only when the network effect is from the same product categories and cross-version, the originals can simultaneously maximize profits and original demand.

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