Registration fees are currently $35 for a Single Work (one image) or $55 for the Standard Application that allows multiple images as long as they were created by the same author in the same year.
Currently in the news, the Copyright Office is proposing a new rule making to increase registration fees www.copyright.gov/rulemaking/feestudy2018 . They want to raise:
Standard application: from $55 to $75
Single application: from $35 to $55
Photographers have a group registration option where they can register up to 750 images on the same registration, but this is not available to illustrators.
AMI is preparing a comment that this rate hike disproportionally hurts visual artists (who create hundreds/thousands of works in a year) and independent creators (who can't afford to register every image) and are already financially impacted by online piracy.
You are correct that there is differing treatment in the courts when works are registered as a "collection" and if the works are registered as "published" or "unpublished." In some cases the statutory awards are fractionally applied to the number of images on the application. For example 100 images registered could potentially only be eligible for 1/100 of a $30,000 award.
Recent certificates from the Copyright Office have been containing a note: Basis for Registration: An unpublished collection, which extends to only each individual copyrightable work in the collection. 17 USC 410(a) and 37 CFR 202.3(b)(4)(i)(B).
In short, it's not clear what this means. AMI will be putting this discrepancy in the official comment to the Copyright Office.
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