Effective April 2019 and with update 2019/23, Derwent World Patents Index (DWPI; STNext file labels WPINDEX, WPIDS and WPIX) and the Derwent Markush Resource (file label DWPIM) will be updated twice a week. For 2019, this means there will be 99 updates as compared to 83 last year, and 104 updates are expected for 2020. More frequent updating will allow more timely delivery of new and updated records, and will allow DWPI and DWPIM to keep pace with increasing global patent volumes. Results from STN alerts set to run at every update will be delivered on the new twice-weekly schedule. Alerts set to run weekly or monthly will not be affected by the change.