“post-effective period”是美国IPO注册登记三个阶段中的其中一个阶段。

一九三三年证券法1933 Securities Act 规定，美股注册登记有三个阶段，分别是 1.向证管会申报注册登记表前之阶段(pre-filing period)：在公司上SEO提交注册申请之前的30天之内，不能给出offer；2.申报注册登记表及其正 式 生 效 间 的 等 待 期 间 (waiting period)：发行人可以做出口头offer，但是发行人不能做出除募股说明书外的书面offer； 3.注册登记表生效后阶段(post-effective period)。 题主所问的正是第三个阶段，注册登记表生效后阶段(post-effective period)，也可译为注册登记表生效后期间或生效后期间。具体而言，这一期间指的是美国证券交易委员会宣布注册登记表有效开始至承销商或经纪商无需根据一九三三年证券法提交招股说明书之日止的期间，其具体英文释义如下，供参考：

Post-Effective Period.The post-effective period begins when the registration statement is declared effective by the SEC and ends when underwriters or broker-dealers are no longer required to deliver a prospectus by the Securities Act of 1933 (the "Securities Act") (which is essentially 25 days after the registration statement is declared effective for an IPO). During the post-effective period, sales are permitted and certain communications, such as free writing prospectuses, are allowed. However, a free writing prospectus of an IPO issuer must be accompanied or preceded by a final prospectus.

以下为相关双语示例：

That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

为确定《证券法》项下的任何责任，每份生效后修正案应被视为与据其所发行的证券有关的新注册说明书，且该等证券届时的发行应被善意视为首次发行。