Space Weather and Commercial Property Insurance

Space Weather Exclusion

Insurance Services Office, Inc. (ISO), has recently introduced an endorsement, Space Weather Exclusion (CP 10 79 06 26). The endorsement is effective beginning in June 2026 and is considered mandatory according to ISO rules. The endorsement adds the following exclusion, prefaced with anticoncurrent causation language, to commercial property policies.

The following exclusion is added:

We will not pay for loss or damage caused directly or indirectly by the following. Such loss or damage is excluded regardless of any other cause or event that contributes concurrently or in any sequence to the loss.

Space Weather

Space weather, meaning any condition or event originating beyond the Earth's upper atmosphere that interacts with Earth's magnetosphere, ionosphere, thermosphere or upper atmosphere, that disrupts or otherwise interferes with property that is space-borne, atmospheric or ground-based. Such condition or event includes, but is not limited to, solar wind, space particles, space electromagnetic radiation, solar energetic proton events, high-speed solar wind streams, coronal mass ejections, solar flares or geomagnetic storms.

Source: Insurance Services Office, Inc., Space Weather Exclusion (CP 10 79 06 26), © 2026.

It is interesting to note that, unlike some other exclusions that follow anticoncurrent causation language, there is no exception for damage by fire that may result from the excluded peril. Because, in some jurisdictions, coverage for loss by ensuing fire must be preserved, ISO has introduced a second endorsement, Space Weather Exclusion with Ensuing Cause of Loss Exception (CP 10 80 06 26), which adds the following language to the exclusion.

B. Exception Covering Certain Fire Losses

If a space weather condition or event results in fire, we will pay for the loss or damage caused by that fire. Such coverage for fire applies only to direct loss or damage by fire to Covered Property. Therefore, for example, the coverage does not apply to insurance provided under Business Income and/or Extra Expense coverage forms or endorsements which apply to those forms, or to the Legal Liability Coverage Form or the Leasehold Interest Coverage Form.
Source: Insurance Services Office, Inc., Space Weather Exclusion with Ensuing Cause of Loss Exception (CP 10 80 06 26), © 2026.

Note that this exception applies only to direct damage by fire, not to any time element loss, such as business income or extra expense. For many commercial insureds, these indirect losses are likely to cause more financial harm than that caused by fire damage resulting from space weather.

Special Form Causes of Loss Exclusions

There are two exclusions in the Causes of Loss—Special Form (CP 10 30 09 17) that already remove coverage for much of the direct and indirect loss caused by space weather: nuclear hazard and utility services.

Nuclear Hazard

One of the concerns with space weather is the effect that radioactive material may have on satellite operations as well as communication and navigation systems. The National Oceanic and Atmospheric Administration (NOAA) has created Space Weather Scales to describe the effect of current and future space weather conditions on people and systems.¹

Solar radiation storms are rated on a scale of S1 to S5, with S1 having only a minor impact on high-frequency radio in the polar regions. S5 results in satellites that are rendered useless and a complete blackout of high-frequency communications through the polar regions, along with position errors that make navigation operations extremely difficult.

Even without the Space Weather Exclusion, the ISO special form's nuclear hazard exclusion applies to losses involving nuclear reaction or radiation, or radioactive contamination, however caused; the exclusion is prefaced with anticoncurrent causation language.

One important difference between the nuclear hazard exclusion and Space Weather Exclusion (CP 10 79 06 26) is that the nuclear hazard exclusion has an exception for damage by ensuing fire, while the Space Weather Exclusion does not.

Utility Services

One of the biggest exposures to commercial insureds after a space weather event is the loss of power. Even without the Space Weather Exclusion, the ISO special form excludes power failure with the utility services exclusion, an exclusion prefaced with anticoncurrent causation language. The exclusion removes coverage for loss caused by the failure of power, communication, water, or other utility service supplied to the described premises. The exclusion applies when the failure originates away from the described premises or originates at the described premises and involves equipment used to supply the utility service from an off-premises source.

The utility services exclusion has an exception for damage by ensuing covered causes of loss, while the Space Weather Exclusion (CP 10 79 06 26) does not.

Also, it is common for commercial property policies to add back some coverage for utility services interruption through endorsements such as Utility Services—Direct Damage (CP 04 17 10 12) and Utility Services—Time Element (CP 15 45 09 17). With the Space Weather Exclusion, loss of power due to space weather is not a covered cause of loss, so the endorsements will not provide coverage.

Conclusion

Concerns over space weather and its effect on commercial insureds are not new. Based on the exclusions already in ISO forms, it is unlikely that coverage would apply to many losses involving space weather. However, ISO's new endorsement makes it clear that the property policies commonly written do not intend to respond to any direct or indirect losses involving space weather.