????希爾德的發(fā)現(xiàn)是基于系統(tǒng)研究亞馬遜網(wǎng)站上新書（與舊書相對(duì)）的多寡而得的，它揭示了19世紀(jì)50年代出版的書與20世紀(jì)50年代出版的書在可獲得性上的巨大差異，盡管后一個(gè)時(shí)期中出版的書要多得多。這項(xiàng)研究中的一張圖表更是清晰地表明，“在公共領(lǐng)域版權(quán)到期的1923年之前，亞馬遜網(wǎng)站上有數(shù)量驚人的初次出版的新書，而在1923年之后，亞馬遜首次出版的書數(shù)量則急劇下降。”

????而與此同時(shí)，為版權(quán)保護(hù)積極游說的利益團(tuán)體則“在缺乏實(shí)證證據(jù)支撐的情況下辯稱，一旦作品進(jìn)入公共領(lǐng)域，就會(huì)遭到侵害。按照這種理論，是公共利益要求延長版權(quán)保護(hù)期，以防止公共領(lǐng)域出現(xiàn)版權(quán)災(zāi)難。”

????這些游說者的說法是建立在缺乏經(jīng)濟(jì)常識(shí)的理論基礎(chǔ)上的：即所謂的從根本上說，像書籍、電影和音樂這類傳媒產(chǎn)品的市場(chǎng)必須形成壟斷才能有效運(yùn)轉(zhuǎn)。他們說，如果任何人都能銷售小說或電影，人們就會(huì)一擁而上爭(zhēng)相復(fù)制生產(chǎn)，導(dǎo)致價(jià)格急劇下跌。但是正如希爾德所指出的，盡管可能會(huì)出現(xiàn)競(jìng)爭(zhēng)，但并不會(huì)妨礙它們的開發(fā)利用，繩子、牛奶、鉛筆等不存在壟斷的商品就是這樣?！倍倚枰赋龅氖?，上述商品都沒有受到有任何時(shí)限的專賣權(quán)保護(hù)，更別提幾十年的保護(hù)期了。

????版權(quán)當(dāng)然是必須要有的，這樣創(chuàng)作者才能掙回成本，獲得不錯(cuò)的回報(bào)——這就能提供創(chuàng)造動(dòng)力了。但這并不意味著版權(quán)所有人應(yīng)該一直緊抓著自己的版權(quán)不放，非要到作品已無法在市場(chǎng)流通為止。

????希爾德的這篇論文還提到了《數(shù)字千年版權(quán)法》（Digital Millennium Copyright Act）的“安全港”這個(gè)條款，探討了它如何讓經(jīng)典老歌能繼續(xù)在YouTube上傳播的原因。YouTube為版權(quán)所有者提供了一條從自己擁有的歌中輕松生財(cái)?shù)姆奖阒溃呐逻@些歌已被侵權(quán)人給上傳了。這樣就算這些歌無法從其他渠道獲得，也能“滿足潛在樂迷的市場(chǎng)”。（財(cái)富中文網(wǎng)）

????譯者：清遠(yuǎn)

????Heald's findings, based on a systematic study of availability of new (as opposed to used) books on Amazon, revealed the immense difference between books published in the 1850s and those from the 1950s despite the fact that many more books were published in the latter decade. And, as a chart included with his study starkly reveals, there is an "eye-poppingly disproportionate number of new Amazon books initially published before the public domain cut-off date of 1923 and new Amazon books initially published after 1923."

????Meanwhile, copyright lobbyists "argue -- without empirical support -- that bad things happen to the work when it falls into the public domain. The public interest, so the story goes, requires term extension to prevent a public domain calamity."

????Those lobbyists pin their arguments on theories that make no economic sense: essentially, that the market for media products like books, films, and music needs to be a monopoly in order to function. If anybody can market a given novel or film, they argue, then too many people will produce copies, driving down the price. But as Heald notes, despite "potential competition, exploitation will occur, just as it does in other markets where no one has a monopoly over the object of exploitation, e.g. the markets for string, milk, and pencils." And none of those things, it should be noted, are protected with exclusive sale rights for any amount of time, much less for decades-long stretches.

????Copyright of course is needed so that originators can earn back their costs and make a decent profit -- that's what provides the incentive to create. But that doesn't mean rights-holders should be able to hold their rights to the point where works are actually removed from the marketplace.

????Heald's paper also looks at how the "safe harbor" provisions of the Digital Millennium Copyright Act help keep older songs in circulation on YouTube (GOOG). YouTube offers an easy way for copyright holders to make money from the songs they own, even when they've been uploaded by infringers, and thus "satisfy the market of potential listeners" even when the songs aren't otherwise available.