| Goodwill and intangible assets Goodwill and intangible assets deemed to have an indefinite life are not amortized, but are evaluated annually for impairment as part of our annual business planning cycle in the fourth fiscal quarter, or when indicators of a potential impairment are present.
The following table sets forth goodwill by segment as of October 1, 2022 and March 31, 2023:
| | | | | | | | | | | | | | | | | | | Batteries & Lights | | Auto Care | | Total | | Balance at October 1, 2022 | $ | 868.9 | | | $ | 134.2 | | | $ | 1,003.1 | | | Cumulative translation adjustment | 16.4 | | | — | | | 16.4 | | | Balance at March 31, 2023 | $ | 885.3 | | | $ | 134.2 | | | $ | 1,019.5 | |
Energizer had indefinite-lived intangible assets of $763.4 at March 31, 2023 and $762.5 at September 30, 2022. The difference between the periods is driven by currency adjustments. Total intangible assets at March 31, 2023 are as follows:
| | | | | | | | | | | | | | | | | | | Gross Carrying Amount | | Accumulated Amortization | | Net Carrying Amount | | | | | | | | Trademarks and trade names | $ | 142.4 | | | $ | (25.5) | | | $ | 116.9 | | | Customer relationships | 394.3 | | | (126.6) | | | 267.7 | | | Patents | 34.0 | | | (16.9) | | | 17.1 | | | Proprietary technology | 172.5 | | | (91.3) | | | 81.2 | | | Proprietary formulas | 29.2 | | | (8.2) | | | 21.0 | | | | | | | | | Vendor relationships | 7.6 | | | (7.6) | | | — | | | Total Amortizable intangible assets | 780.0 | | | (276.1) | | | 503.9 | | | Trademarks and trade names - indefinite lived | 763.4 | | | — | | | 763.4 | | | Total Other intangible assets, net | $ | 1,543.4 | | | $ | (276.1) | | | $ | 1,267.3 | |
Total intangible assets at September 30, 2022 were as follows:
| | | | | | | | | | | | | | | | | | | Gross Carrying Amount | | Accumulated Amortization | | Net Carrying Amount | | | | | | | | Trademarks and trade names | $ | 141.8 | | | $ | (21.4) | | | $ | 120.4 | | | Customer relationships | 393.5 | | | (112.6) | | | 280.9 | | | Patents | 33.4 | | | (15.7) | | | 17.7 | | | Proprietary technology | 172.5 | | | (81.5) | | | 91.0 | | | Proprietary formulas | 29.2 | | | (6.3) | | | 22.9 | | | | | | | | | Vendor relationships | 6.9 | | | (6.5) | | | 0.4 | | | Total Amortizable intangible assets | 777.3 | | | (244.0) | | | 533.3 | | | Trademarks and trade names - indefinite lived | 762.5 | | | — | | | 762.5 | | | Total Other intangible assets, net | $ | 1,539.8 | | | $ | (244.0) | | | $ | 1,295.8 | |
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