IMDS Data Quality Problems: Why Automotive Material Declarations Often Fail Compliance Reviews

The MDS was submitted. The OEM rejected it.

An automotive supplier spends hours building a Material Data Sheet in IMDS, structuring the assembly tree, classifying materials, entering substance percentages, and sending it to their OEM customer. Two weeks later, the MDS comes back rejected.

The rejection reasons are familiar: the polymer entry contains only one substance. The tree hierarchy doesn't mirror the physical product structure. A GADSL-declarable substance is missing from the material composition. The calculated weight doesn't match the measured weight. The recyclate content question wasn't answered for a material weighing more than 5 grams.

The supplier fixes the errors, resubmits, and waits again. Meanwhile, the Production Part Approval Process (PPAP) is on hold, production timelines are slipping, and the compliance team is firefighting instead of managing their broader material disclosure programme.

IMDS data quality failures are the single most common bottleneck in automotive supplier compliance. With the IMDS 15.2 release rolled out on January 21, 2026, introducing stricter validation for SVHC and GADSL substance reporting, the bar for submission quality has risen again. IMDS 15.3, released on May 11, 2026, further improved search, analysis, and navigation capabilities within the MDS tree. OEMs like Bosch now require MDS submissions at least six weeks before PPAP. Volvo Group publishes formal rejection guides for suppliers. And auto-rejection rules, where OEMs pre-define acceptance criteria and any deviation triggers automatic rejection, are becoming standard across the industries.

This article examines the most common IMDS submission failures, what changed with IMDS 15.2, and how suppliers can build a material declaration process that passes OEM compliance reviews consistently.

What IMDS Requires: The Basics That Trip Suppliers Up

The International Material Data System is the automotive industry's centralised platform for managing material composition data. Originally developed in response to the EU End-of-Life Vehicles Directive (2000/53/EC), IMDS is now the standard mechanism for tracking material content across the entire automotive supply chain, supporting compliance with ELV, REACH, SCIP, GADSL, RoHS (for electronic components), and regional regulations including California Proposition 65 and China RoHS. A provisional agreement on a new ELV Regulation to replace the original Directive was reached in December 2025 and endorsed by Coreper in February 2026; once formally adopted, the new Regulation will further strengthen recycled content and circularity requirements for vehicles.

Every part supplied to an automotive OEM requires a Material Data Sheet (MDS) submitted through IMDS. The MDS must declare the complete material composition of the part, structured as an assembly tree that mirrors the physical product hierarchy: assemblies, semi-components, materials, and substances.

Key requirements that create the most compliance friction:

1. 100% material disclosure. Every substance in every material must be accounted for. IMDS requires Full Material Declarations (FMD), not partial compositions. Minor additives, processing aids, and impurities must all be declared. Substances not restricted or declarable under GADSL can be grouped under wildcards like "Misc. not to declare," but their weight percentages must still be captured.
2. Proper material classification per IMDS Recommendation 001 (REC 001). Every material must be assigned a classification from IMDS's standardised list (metals, polymers, ceramics, glass, natural materials, etc.). Unclassified materials are no longer accepted as of IMDS 14.3. Polymer materials must contain at least two substances (per REC 001 section 4.5.4). Note: REC 001 was most recently updated effective April 24, 2026; a new Recommendation 026 (Regulatory Information) also became valid on the same date. Suppliers should review the latest version for any changes to section numbering or requirements.
3. GADSL substance declaration. Substances on the Global Automotive Declarable Substance List must be declared by name and CAS number when present above the specified thresholds. GADSL includes substances that are prohibited (must not be present) and declarable (must be reported if present above threshold). The most recent GADSL update was implemented in IMDS on March 20, 2026, flagging additional substances; suppliers should verify they are working with the latest GADSL version.
4. Weight accuracy. The calculated weight of the MDS (sum of all constituent material weights) must match the measured weight of the physical part within acceptable tolerances. Weight discrepancies are one of the top five rejection reasons across OEMs.

The Seven Most Common IMDS Rejection Patterns

1. Incomplete material disclosure (the "100% rule" violation)

The most fundamental failure: a material entry doesn't account for 100% of its composition. Suppliers omit minor additives, stabilisers, pigments, or processing aids, leaving a gap between the declared substance percentages and 100%. OEMs reject these submissions because incomplete disclosure creates blind spots for restricted substance tracking.

The fix is structural: work with raw material suppliers to obtain complete composition data, including "Misc. not to declare" wildcards for non-restricted substances that round out the total to 100%.

2. Polymer entries with only one substance

Per IMDS REC 001, a polymer material (classification 5.x) must contain at least two substances. No material is ever 100% of a single substance; impurities, stabilisers, or processing residues are always present at some level. A submission listing PA6 at 100% without any secondary substances will be flagged by IMDS and rejected by the OEM.

This is one of the most common errors for suppliers who create their own material entries rather than using IMDS Committee Published Materials or requesting proper material data from their raw material suppliers.

3. Assembly tree structure doesn't mirror the physical product

IMDS requires the MDS tree to reflect the actual physical hierarchy of the part: assemblies contain semi-components, which contain materials, which contain substances. Suppliers who build flat structures (all materials at one level) or who create unnecessary hierarchy levels (placeholder assemblies with no physical counterpart) trigger rejections.

Bosch's March 2026 IMDS guideline explicitly requires suppliers to "familiarize yourself with our IMDS guideline" and warns that "preliminary material data sheets may contain incomplete information on materials" and cannot be used for PPAP approval.

4. Missing or incorrect GADSL substance declarations

When a GADSL-declarable substance is present in a material above its declaration threshold, it must be listed by name and CAS number. Suppliers who are unaware of GADSL requirements, or who use outdated GADSL versions, submit MDS entries that omit declarable substances. OEMs running automated compliance checks will flag and reject these submissions.

IMDS 15.2 strengthened this area: for substances listed on the SVHC Candidate List or marked as prohibited or declarable under GADSL, the use of a generic "rest" portion is no longer permitted. Every SVHC and GADSL substance must be explicitly declared.

5. Weight discrepancies between calculated and measured values

The total calculated weight of all materials in the MDS must match the measured weight of the physical part. Discrepancies arise from rounding errors across multiple material entries, from using estimated weights during prototyping that were never updated for production, or from omitting lightweight components (labels, adhesives, surface treatments) that contribute to total weight.

Volvo Group lists weight variance as one of nine common IMDS rejection reasons for their suppliers, and most OEMs set tolerances between 2% and 10% depending on part complexity.

6. Missing recyclate content declaration

IMDS requires suppliers to answer whether each material contains recyclate ("Does the material contain recyclate?"). For materials weighing more than 5 grams referenced in a component, this question must be answered "yes" or "no." Leaving it unanswered triggers a validation warning and may lead to OEM rejection.

This requirement has become more prominent with the EU's circular economy focus. The EU Battery Regulation's recycled content requirements mandatory recycled content declarations from August 2028, minimum thresholds from 2031) and the End-of-Life Vehicles Regulation revision are both increasing OEM scrutiny on recyclate data in IMDS.

7. Failure to use IMDS Committee Published Materials

IMDS maintains a library of Committee Published Materials: pre-validated material entries for common materials that suppliers can reference directly. Suppliers who create their own entries for standard materials (like common steel alloys or standard polymers) instead of using the published versions introduce inconsistencies, because their custom entries may use different classification codes, different substance breakdowns, or different naming conventions.

OEMs prefer (and in some cases require) that suppliers use Committee Published Materials wherever available. Custom entries for materials where published versions exist are a common rejection trigger.

What Changed with IMDS 15.2 (January 2026) and IMDS 15.3 (May 2026)

IMDS 15.2, rolled out to production on January 21, 2026, introduced targeted changes that raise the data quality bar. IMDS 15.3, which went live on May 11, 2026, builds on these changes with further usability and analysis improvements.

No "rest" portion for SVHC and GADSL substances The most impactful change. Previously, suppliers could use a generic "rest" portion that might implicitly contain SVHC or GADSL substances without declaring them individually. IMDS 15.2 eliminates this. Every SVHC and GADSL substance must be explicitly named and declared, with no hiding behind aggregate wildcards.

Ceramics and glass exempt from BPR. Materials classified as ceramics or glass (classification 7.2) no longer require Biocidal Products Regulation (BPR) information. Existing BPR data for these materials remains valid, and open BPR update requests are automatically closed. This reduces unnecessary data entry for suppliers of glass and ceramic components.

Strengthened substance transparency. Suppliers can now use new "confidential marking" structures for proprietary substances while still ensuring regulatory thresholds (like 0.1% w/w for SVHCs) are assessed correctly. This balances trade secret protection with regulatory compliance.

Updated IMDS check message. The revised system message clarifies that a successful IMDS check does not automatically guarantee full regulatory or customer-specific compliance, highlighting the continued need for manual review.

OEM auto-rejection capabilities. While not a system feature of 15.2 specifically, the trend has accelerated: OEMs and Tier-1 suppliers can now pre-define MDS acceptance criteria within their workflows. Any deviation (missing weight, inconsistent structure, undeclared substances) leads to auto-rejection without manual review. Suppliers submitting incomplete MDS entries will see faster, more frequent rejections.

IMDS 15.3 Key Changes (May 11, 2026):

IMDS 15.3 focuses on usability and data analysis improvements rather than new regulatory requirements. Key enhancements include new filter options (such as Chemical Presence Type) for more precise substance evaluation, improved MDS tree navigation with "Expand selected node" functionality, and additional search and analysis capabilities. While 15.3 does not introduce major structural changes, it reinforces the platform's ongoing evolution toward better data quality and process reliability. 

The practical implication of IMDS 15.2 & 15.3 is clear: older MDS submissions that passed validation under previous versions may now be flagged under stricter rules. Suppliers should review existing submissions for compliance with the updated SVHC/GADSL declaration requirements.

Why IMDS Failures Are Getting More Expensive

PPAP delays cascade through the supply chain

An IMDS rejection delays the PPAP approval for the affected part. In a just-in-time automotive supply chain, PPAP delays can cascade into production line shutdowns, launch postponements, and penalty clauses. The cost of an IMDS rejection is not the time spent fixing the MDS; it's the downstream production impact.

OEM rejection patterns are becoming automated

OEMs are shifting from manual MDS review to automated acceptance criteria. This means rejections are faster, more systematic, and harder to negotiate around. A submission that might have been accepted with a note under manual review is now auto-rejected without discussion.

Regulatory scope is expanding through IMDS

IMDS was originally built for ELV compliance. It now supports REACH SVHC tracking, SCIP database data preparation, GADSL reporting, RoHS (through ELV harmonisation), California Proposition 65, and emerging recycled content requirements. Each regulatory layer adds data fields that must be correctly populated. The complexity of a compliant MDS submission has grown substantially, while the tolerance for errors has shrunk.

Building an IMDS Process That Doesn't Break

1. Collect FMD data from raw material suppliers, not just Tier-1 declarations

The most common root cause of IMDS failures is insufficient upstream data. Ensure your raw material suppliers provide full material composition with CAS numbers, weight percentages, and GADSL/SVHC substance identification. Without this data, your IMDS entries are educated guesses.

2. Use Committee Published Materials wherever available

Check the IMDS library before creating custom material entries. Published materials are pre-validated against REC 001 and reduce the risk of classification errors, single-substance polymer failures, and naming inconsistencies.

3. Validate assembly tree structures against physical BOMs

Build a process where engineering and compliance teams jointly review IMDS tree structures against the actual product BOM. The tree should mirror the physical product hierarchy exactly: no placeholder levels, no flattened structures, no missing sub-assemblies.

4. Implement pre-submission validation checks

Run IMDS validation before sending it to the OEM. Check for: 100% material disclosure, polymer entries with at least two substances, GADSL substance declarations for all restricted and declarable substances above threshold, weight accuracy within OEM-specified tolerances, and recyclate content declarations for all materials above 5 grams.

5. Track OEM-specific guidelines and update processes accordingly

Each OEM publishes its own IMDS guidelines with specific requirements beyond the IMDS standard. Bosch's March 2026 guideline, for example, requires submissions six weeks before PPAP and mandates compliance with their internal substance standard N2580. Volvo publishes a formal rejection guide. Build OEM-specific checklists that your team runs before each submission.

6. Review existing MDS entries against IMDS 15.2 changes

The elimination of "rest" portions for SVHC/GADSL substances means that older MDS submissions that used aggregate wildcards for restricted substances may now fail. Audit your active MDS inventory for entries that relied on this practice and update them proactively.

7. Verify compliance against the latest REC 001 and Recommendation 026

IMDS Recommendation 001 (General Structure) was updated effective April 24, 2026, and a new Recommendation 026 (Regulatory Information) also became valid on the same date. Suppliers should review the latest versions of both recommendations to ensure current MDS entries and workflows align with any updated rules, section numbering, or reporting requirements.

A Self-Check for Your IMDS Process

Seven questions to pressure-test your material declaration programme:

●      Recommendation currency: Am I working against the latest IMDS Recommendations (REC 001 updated April 2026, new REC 026) and the most recent GADSL version (updated March 2026)?

●      Upstream data quality: Do my raw material suppliers provide full material composition with CAS numbers and weight percentages, or am I building IMDS entries from incomplete data?

●      Published materials usage: Am I using IMDS Committee Published Materials for standard materials, or creating custom entries that introduce inconsistency risk?

●      GADSL/SVHC compliance: For materials containing GADSL-declarable or SVHC substances, have I explicitly declared each substance by name (no "rest" portion), per IMDS 15.2 requirements?

●      Weight accuracy: Do my calculated MDS weights match measured part weights within OEM-specified tolerances?

●      OEM alignment: Have I reviewed the IMDS guidelines for each OEM I supply (Bosch, Volvo, BMW, etc.) and built OEM-specific submission checklists?

●      Recyclate content: Have I answered the recyclate content question for all materials above 5 grams?

If more than two answers reveal gaps, your IMDS submissions are at elevated risk of rejection under the stricter validation environment of IMDS 15.2 & 15.3

Where Regilient fits in

IMDS data quality is not a training problem. It's a data architecture problem. Suppliers with hundreds of parts, thousands of materials, and dozens of OEM customers need a system that validates material composition data before it reaches IMDS, not after it gets rejected.

Regilient's agentic sustainability platform automates the parts of IMDS compliance that generate the most rejections:

●      Automated material composition validation against REC 001 classification rules, 100% disclosure requirements, and minimum substance count rules for polymers

●      GADSL and SVHC substance screening that identifies declarable and prohibited substances in material composition data before MDS creation, aligned with IMDS 15.2 requirements

●      Weight reconciliation that cross-checks calculated MDS weights against measured part weights and flags discrepancies before submission

●      OEM-specific compliance profiles that apply Bosch, Volvo, BMW, and other customer-specific IMDS requirements as pre-submission validation rules

●      Supplier FMD collection workflows that request and validate full material declarations from upstream suppliers with CAS-level substance data

Every IMDS rejection costs time, delays PPAP, and risks production schedules. The suppliers who validate material data before it enters IMDS will submit once and pass. The suppliers who validate after rejection will submit repeatedly and fall behind.

Book a Regilient demo to see how agentic IMDS compliance validates material declarations before submission, not after rejection.

Regilient provides agentic sustainability software for product compliance, supplier engagement, and regulatory intelligence across REACH, RoHS, PFAS, CMRT, SCIP, and global chemical regulations.