Can a Folding Bike Lock Earn ART 3 Certification?

ART 3 certification is the independent security standard required for high-risk bicycles and e-bikes in the Netherlands, where over 86,000 bikes were officially reported stolen in 2024.² Most locks never reach this rating, and for years no folding lock had managed it. The bike lock certifications guide covers how ART fits alongside Sold Secure, FUB, and Varefakta. This article goes deeper on one specific question: what does it actually take for a folding lock to earn ART 3, and which locks have done it?

Key Takeaways

• ART 3 is the first certification level required by Dutch insurers for high-risk bicycles and e-bikes, a meaningful step above the ART 2 minimum for standard bikes.
• All ART-certified locks are tested by SKG-IKOB, an independent Dutch laboratory, across 20-plus categories covering cutting, leverage, freezing, corrosion, endurance, and lock-picking.
• Folding locks face a structural challenge at ART 3: every hinge joint must resist the same attack tools as the steel plates, not just the lock body.
• The Foldylock Forever and Foldylock Elite are the only folding bike locks to hold ART 3 certification, both also carrying Sold Secure Gold.
• ART 3 is the first level originally designed for scooters and mopeds, meaning certified folding locks are held to a motorized-vehicle standard.

What Is ART Certification and Who Issues It?

ART stands for Algemeen Reglement Tweewielers, which translates roughly as the General Regulation for Two-Wheelers. It is an independent Dutch foundation with one purpose: testing bicycle and motorcycle security products against standardized, independently administered theft-resistance criteria. The foundation has no commercial interest in the locks it certifies. It does not sell locks, endorse brands, or license its mark in return for payments. A lock either passes the testing protocol or it does not.

The foundation has established itself as the benchmark standard in the Netherlands and is recognized across a growing number of European markets. Dutch bicycle insurers use ART ratings as a direct requirement for coverage, which gives the certification real financial consequences for cyclists. A lock that fails ART testing cannot be used to satisfy an insurance policy's minimum security requirement, no matter how the manufacturer describes it internally.

All testing is carried out by SKG-IKOB Certificatie BV, an accredited independent Dutch laboratory. SKG-IKOB works across many product categories, from bullet-resistance systems to door hardware to mechanical anti-theft devices. Its involvement with ART is what gives the certification genuine third-party status: the manufacturer submits a production sample of the lock, SKG-IKOB subjects it to the full protocol, and the result is determined without any manufacturer input on the outcome. The manufacturer cannot appeal a failed test by submitting a different sample or changing the test conditions.

The ART star system runs from 1 to 5. Each level represents a distinct tier of protection, not just a marginal increment:

• ART 1: Basic deterrence against opportunistic theft. The lock deters someone from simply walking off with an unsecured bike. Suitable for short stops in lower-risk environments.
• ART 2: Standard protection for regular bicycles. The minimum level most Dutch bicycle insurance policies accept for coverage. Tests are more demanding than ART 1 but below the threshold required for higher-value or higher-risk vehicles.
• ART 3: Protection designed for high-risk bicycles, e-bikes, scooters, and mopeds. Required by Dutch insurers for these vehicle categories. Tests add specialized attack methods not included at ART 2.
• ART 4: Designed for road motorcycles. Requires resistance against heavier tools and longer attack durations than any bicycle lock would need to meet.
• ART 5: Designed for stationary motorcycle use. The most demanding tier. Tested with heavier tools and extended attack periods. Generally too heavy for a cyclist to carry.

The distinction between ART 2 and ART 3 is not simply a matter of degree. ART 3 was built to address the threat environment faced by higher-value vehicles and attracts more determined thieves than the casual opportunist an ART 2 lock deters. The testing criteria reflect that.

One detail that is easy to miss: ART 3 was originally designed for scooters and mopeds, not bicycles. When a folding bike lock earns ART 3, it is meeting a standard created for motorized vehicles. That context matters. It helps explain why the certification is rare in the folding-lock category, and why reaching it represents a genuine engineering achievement, not a marketing position.

How Does ART Testing Work?

The ART testing protocol covers more than 20 separate assessments administered by SKG-IKOB. Attack resistance is the most visible part, but a lock must clear every category. A sample that excels at resisting bolt cutters but fails the corrosion or endurance test does not earn the certification.

The full battery of tests includes:

• Freezing test: The lock is subjected to low temperatures to assess whether the steel becomes brittle or the cylinder mechanism becomes vulnerable to cracking attacks. A lock that holds at room temperature but fractures when frozen is not street-ready in a northern European winter.
• Dust test: Particulate contamination is introduced into the mechanism to assess whether it causes the cylinder to jam or seize. Locks used outdoors daily accumulate dust, road grime, and fine debris over months.
• Corrosion test: The lock is exposed to salt spray conditions to simulate years of outdoor use. Rust that degrades the cylinder or the steel links creates attack points that a thief can exploit.
• Endurance test: The cylinder and locking mechanism are cycled through thousands of lock-unlock repetitions. A cylinder that wears prematurely may become easier to pick or bypass.
• Tensile strength test: The shackle, link chain, or folding plates are subjected to measured pull force to assess the maximum load before failure.
• Sawing test: A handsaw is applied to the lock material for a defined period. Hardened steel generates significant heat during sawing, which slows the attack but does not stop it. The test measures how long the material holds.
• Bolt-cutter test: Bolt-cutter jaws are applied to the lock body, shackle, or links to assess resistance to this common street attack. The lever advantage of long-handled bolt cutters generates substantial force at the cutting edge.
• Leverage test: A pry bar is used to apply lever force to the lock body and joints. This tests whether the mechanism or connecting hardware can be separated by mechanical force rather than cutting.
• Lock-picking test: Specialized picking tools are applied to the cylinder for a defined period. At ART 3, this test is included as part of the standard assessment, meaning the cylinder must resist both brute-force attacks and technical bypass methods.

"An ART 3 lock provides quality protection against theft for bikes with a high risk of being stolen, as well as for scooters and mopeds."

Stichting ART, the Netherlands' independent bicycle security certification body¹

The test report that follows a successful assessment is assigned a unique four-digit code. That code appears alongside the star rating on every lock that earns the certification. Cyclists, insurers, and theft-prevention advisors can use it to verify that a specific product was assessed by SKG-IKOB, not just claimed by the manufacturer to meet a particular standard. The public registry on the Stichting ART website allows anyone to search by product name or test code.

What Does ART 3 Certification Specifically Require?

The difference between ART 2 and ART 3 is not simply an incremental increase in the same tests. ART 3 adds test categories and extends the attack duration in others, reflecting the assumption that a thief targeting a high-value bike or moped is more motivated and better equipped than someone targeting a standard commuter bicycle.

At ART 2, the attack resistance tests are calibrated to common opportunistic tools: basic bolt cutters, a hacksaw, and simple leverage. The tests last for a defined period at each attack type, but the tools and techniques assume a relatively unsophisticated attacker with limited time.

At ART 3, the protocol adds specialized lock-picking equipment to the attack battery. The lock cylinder must resist picking attempts for the required duration using tools designed specifically for bypassing security cylinders. This is a meaningful addition because it closes the gap between physical attack resistance and technical bypass. A lock can have 6.5mm steel plates and still fall quickly to a practiced picker if the cylinder is not rated for that threat.

The leverage test is also more demanding at ART 3. The force applied and the test duration are scaled to the assumption of a more motivated attacker. Hinge joints, lock bodies, and the interface between the steel plate and the cylinder housing must all hold under these conditions, not just the steel itself.

For a lock to pass ART 3, every test category must be cleared. There is no partial credit. A lock that resists bolt cutters and sawing but fails the picking test leaves the certification table without a rating. This is what makes ART 3 a meaningful threshold rather than a marketing tier: the protocol does not reward partial performance.

To put this in practical terms: a standard bicycle lock designed to ART 2 would likely fail ART 3 testing at either the picking test or the leverage test on the hinge joints. Reaching ART 3 requires design changes across multiple components, not just a grade-up in the steel specification.

Why Are Folding Locks Harder to Certify at ART 3?

Folding locks present a structural problem that U-locks and chain locks do not. A U-lock is a single continuous steel shackle that closes into a lock body. A chain lock is a series of links whose attack surfaces are distributed evenly along the chain. A folding lock is different: it is made of multiple hardened steel plates connected by riveted hinge joints, and each joint is a potential attack point that must pass the same tests as the steel plates themselves.

A typical folding lock has between six and nine plates. That means five to eight hinge joints. Each joint must resist the leverage test, the prying attack, and the freezing test. A joint that fails at any of these does not just expose one section of the lock. It potentially compromises the locking arc, the tension across the cylinder, or the structural continuity of the whole assembly. This is why achieving ART 3 with a folding lock is meaningfully harder than achieving it with a U-lock of the same steel grade.

The practical implication: most folding locks fail ART 3 testing not because the steel is too thin, but because the hinge joint construction does not hold under the leverage test or the drilling attack. Reaching ART 3 requires the manufacturer to engineer the joint, not just select a steel specification. That is an in-house design challenge, not a material procurement decision.

Which Folding Locks Currently Hold ART 3?

Two folding locks currently hold ART 3 certification: the Foldylock Forever and the Foldylock Elite. Both are manufactured by Seatylock (Ino-Vision Ltd.) and were independently tested by SKG-IKOB under the ART foundation's protocol.

The Foldylock Forever uses hardened steel plates up to 6.5mm thick, patented anti-tamper rivets, and extends to a 90cm locking circumference. When folded, it measures 20.5cm x 6.9cm x 4.7cm, light enough to mount on a frame bracket without noticeable ride impact. The lock comes with three keys, a key registration card for replacement key ordering, and a three-year manufacturer warranty. Independent testing by Bikerumor confirmed it withstands bolt-cutter and hand-saw attacks under real-world destructive testing conditions.⁵

The Foldylock Elite shares the ART 3 certification and the same plate-and-rivet engineering with an updated premium finish and reinforced outer casing. Both locks also carry Sold Secure Gold, the UK's equivalent independent standard. The fact that two separate testing organizations, using separate protocols, reached the same conclusion about the same hardware is a meaningful convergence. It is not a coincidence; it reflects the consistency of the underlying construction.

Both locks also hold FUB Recommande certification from the French cyclists' federation, adding a third independent body's assessment to the same hardware. Holding three independent certifications from testing organizations in three different countries is unusual for any bike lock, and particularly rare for a folding design.

How Does ART Compare to Sold Secure Gold?

ART and Sold Secure are independent certification systems that evaluate bike locks using different protocols, different testing laboratories, and different rating scales. They operate in the same space - independent, third-party attack-resistance testing that is not controlled by the lock manufacturer - but they are not the same certification. Understanding what they share and where they differ helps cyclists interpret both marks accurately.

Does ART Certification Affect Bike Insurance?

In the Netherlands, ART certification is a formal insurance requirement, not a recommendation. Dutch bicycle insurers specify the minimum ART star level as a condition of policy coverage, and the minimum level depends on the bike type and the associated theft risk. Standard bicycles typically require ART 2. High-risk bikes, e-bikes, and high-value bicycles require ART 3.³

The scale of bicycle theft in the Netherlands explains why insurers take these requirements seriously. In 2024, more than 86,000 bikes were officially reported stolen, with Amsterdam accounting for approximately 11,000 of those reports.² Those are reported thefts only. Research suggests that just 40% of Dutch bike thefts are reported to police, which means the total number of stolen bikes in 2023 reached an estimated 928,000.⁴ Dutch insurers paid out 271 million euros in bicycle theft claims in 2023 alone.⁴

Against that backdrop, the ART 3 requirement for high-value bikes is the insurer's assessment of the minimum security level at which they are prepared to accept the financial risk. It is not an aspirational recommendation. Filing a claim with an ART 2 lock when the policy requires ART 3 can result in a denied claim.

For cyclists outside the Netherlands, ART 3 certification still has practical value. It provides an evidence-based reference point that internal brand ratings cannot replicate. Many lock manufacturers use proprietary security scales rated on a 0-to-10 or 0-to-15 basis. These scales are not comparable between brands: a rating of 10/15 from one manufacturer does not measure the same thing as 10/15 from another, because the protocols, test conditions, and criteria are all set internally by the same company selling the lock. ART 3 means the same thing regardless of which manufacturer's lock carries it, because an independent laboratory applied an independent protocol to reach the result.