ACSM (Adobe Content Server Message) and LCPL (Licensed Content Protection License) files both manage digital rights (DRM protection) for eBooks, ensuring access is restricted to authorized users. However, their functions and uses differ significantly. Here's a detailed comparison:
1. ACSM File and LCPL File Overview
1. DRM Protection
ASCM File(Adobe DRM): Used by platforms like Kobo, Nook, Google Play Books, and OverDrive, ACSM files rely on Adobe DRM—a widely adopted, proprietary system requiring an Adobe ID and Adobe Digital Editions (ADE) to access content. It offers strong security and strict control over distribution.
LCPL Files(LCP DRM): LCPL files use LCP DRM, an open-source alternative by Readium. It avoids vendor lock-in and works with various third-party apps without needing a user account. LCP focuses on flexibility and user-friendliness over rigid control.
Adobe DRM prioritizes security and control, while LCP DRM offers a more open, user-centric approach—each serving different needs in digital publishing.
2. File Content and Purpose
ACSM File: ACSM files don’t contain the actual eBook. Instead, they serve as download keys used by Adobe Digital Editions (ADE) to fetch DRM-protected ePub or PDF files. Each ACSM file is tied to an Adobe ID, enforcing DRM restrictions during download.
LCPL File: LCPL files include both the license and the encrypted eBook content. Used with LCP DRM, they allow compatible readers to open the file directly without separate downloads. The license controls usage rights like copying, printing, and lending, and is unlocked via a passphrase or key.
3. File Compatibility
Both ACSM and LCPL files are not actual eBooks but serve as authorization files to verify that you have the rights to download the content. They are used with Adobe-compliant or LCP-compliant software to convert the content into an EPUB or PDF format.
ACSM File: To open and download ACSM files, users need to install ADE and create an Adobe ID to authorize their device. After that, users can drag the acsm file into ADE to start the download. Once the download is complete, the Adobe DRM-encrypted EPUB or PDF can be located by right-clicking the book cover in ADE and selecting 'Show File in Explorer'.
LCPL File: LCPL files can be opened with LCP-compatible apps like Thorium Reader or open-source eReaders such as FBReader, offering flexibility across platforms. For simplicity, we recommend using Thorium Reader: just drag and drop the LCPL file into the app. Once imported, click the three-dot menu and select "Save As" to export the file—typically as LCP-protected EPUB or PDF, depending on the original format.
LCP-protected files can be accessed in Thorium Reader using a passphrase, which is typically provided at the time of purchase or borrowing. Unlike other DRM systems, LCP does not require complex account setups or device authorization limits.
To summarize ACSM vs. LCPL, here's a comparison table:
| Feature | ACSM | LCPL |
|---|---|---|
| Purpose | Authorization file for downloading eBooks | License file for accessing encrypted content |
| Content | Does not contain eBook content; links to Adobe ID | Contains encrypted eBook content directly |
| DRM System | Adobe DRM | LCP DRM |
| Software Required | Adobe Digital Editions (ADE) | LCP-compliant readers (e.g., Thorium Reader, FBReader) |
| Account Requirement | Requires Adobe ID | No account or personal information required |
| File Handling | Opens in ADE, downloads content in EPUB/PDF | Opens directly in LCP-compatible readers |
| Encryption | Content is encrypted by Adobe DRM | Content is encrypted by LCP DRM |
| User Flexibility | Limited to Adobe's ecosystem | Broader compatibility with multiple readers |
2. How to Remove LCP DRM and Adobe DRM?
1. How to Unlock Readium LCP DRM-protected Files?
Regarding Readium LCP DRM version 2.5, no DeDRM solutions can currently break this strengthened DRM. However, Epubor offers a service that can help you back up all your eBooks with LCP DRM, including those protected by Readium LCP DRM version 2.5. To get started, simply click the button below to order the service and send your LCPDF and EPUB files and passphrase to epubor.alice@gmail.com.
Order LCPL Conversion Service Here
Sososofty Archive Mate can help users backup Internet Archive files from lcpl pdf epub to common ePub PDF. You can refer to this guide.
2. How to Remove DRM from Adobe DRM-protected Files?
To remove DRM from Adobe DRM-protected files, first download the ACSM file using ADE or an ACSM plugin, which will convert it into an EPUB or PDF file with Adobe DRM protection. Next, use a DRM removal tool to strip the Adobe encryption from the downloaded EPUB or PDF files. For detailed instructions, consult a step-by-step guide on removing Adobe DRM.
Tips: Adobe DRM can be removed by converting ACSM files directly to EPUB or PDF — no need for Adobe Digital Editions.
Amy Lopez crafts informative articles on eBooks and eReaders, uncovering optimal methods to enhance your eBook reading experience, and eagerly shares her findings with you.
