correctly and rarely meet the required safety standards. [1,2] Frequently, counterfeit components cause a short circuit, overheat, and subsequently catch fire. Manufacturers are liable in such a scenario and face an enormous reputational loss unless they can prove forgery. This topic is highly relevant for forward-looking industries such as electromobility and automatization, since counterfeit battery cells, for example, can result in vehicle fires.Fire-proof postmortem labels could, for example, enable publicly appointed and sworn experts to verify the originality of a product even after a fire. To our knowledge, however, there are currently no suitable marking technologies available to prove beyond doubt the originality of an object after a fire.In forensic science, comprehensive analytical methods have been applied and further developed to characterize fire debris. Examples include gas chromatography coupled with a mass spectrometry detector, [3][4][5] isotopic ratio mass spectrometry, [6,7] capillary electrophoresis, [8][9][10] or vibrational spectroscopic analysis methods, such as Raman or infrared spectroscopy. [11][12][13] All established methods for the characterization of fire residues have in common that they are complicated, as well as time-and cost-intensive, since also partly complex extraction steps of the analyte are necessary. Moreover, they are based exclusively on the analysis of the intrinsic material properties of burned objects, which, however, can change considerably and manifold depending on the fire condition. [14] Conventional anticounterfeiting features, such as miniaturized printed watermarks or quick response (QR) codes, as well as radio-frequency Identification (RFID) chips, show a sufficient performance during the useful life of a product but are unsuitable for postmortem identification as they are to a large extent not fire-proof. There have been attempts to coat RFID chips with anti-fire materials to increase their resistance when exposed to fire. However, tests were successful only up to 250 °C and the tags are limited in that their components decompose thermally above temperatures beyond ≈500 °C. [15] In addition, these tags are in the macroscopic size range and are not suitable for marking components of electronic devices (e.g., microchips).For these reasons, novel approaches are needed to verify the originality of burned electronic devices. Within the last Counterfeit electronic products not only cause financial losses but also come with safety risks. The worst-case failure scenario certainly is a fire event. Since manufacturers are liable for damages and suffer image loss, fire-proof postmortem taggants are needed, enabling differentiation between originals and counterfeits even after a fire incident. This work presents such taggants: optomagnetic supraparticles (SPs), i.e., complex microscale particles composed of luminescent and magnetic nanoparticles (NPs) are generated. Their hybrid nature is pivotal, as magnetic separation can effectively remove the tags from light-absorb...