diff --git a/src/mol-plugin/state/actions/data-format.ts b/src/mol-plugin/state/actions/data-format.ts
index 7e4bbd656f0e3d47097f3c7d73f0960571a448b3..c8eff16e37cb84cb2d61fc5174cff5e74f55f7ab 100644
--- a/src/mol-plugin/state/actions/data-format.ts
+++ b/src/mol-plugin/state/actions/data-format.ts
@@ -13,6 +13,7 @@ import { ParamDefinition as PD } from 'mol-util/param-definition';
 import { Ccp4Provider, Dsn6Provider, DscifProvider } from './volume';
 import { StateTransforms } from '../transforms';
 import { MmcifProvider, PdbProvider, GroProvider } from './structure';
+import msgpackDecode from 'mol-io/common/msgpack/decode'
 
 export class DataFormatRegistry<D extends PluginStateObject.Data.Binary | PluginStateObject.Data.String> {
     private _list: { name: string, provider: DataFormatProvider<D> }[] = []
@@ -139,4 +140,18 @@ export const OpenFile = StateAction.build({
     const b = state.build().to(data.ref);
     // need to await the 2nd update the so that the enclosing Task finishes after the update is done.
     await provider.getDefaultBuilder(ctx, b, state).runInContext(taskCtx)
-}));
\ No newline at end of file
+}));
+
+//
+
+type cifVariants = 'dscif' | -1
+export function guessCifVariant(info: FileInfo, data: Uint8Array | string): cifVariants {
+    if (info.ext === 'bcif') {
+        try {
+            if (msgpackDecode(data as Uint8Array).encoder.startsWith('VolumeServer')) return 'dscif'
+        } catch { }
+    } else if (info.ext === 'cif') {
+        if ((data as string).startsWith('data_SERVER\n#\n_density_server_result')) return 'dscif'
+    }
+    return -1
+}
\ No newline at end of file
diff --git a/src/mol-plugin/state/actions/structure.ts b/src/mol-plugin/state/actions/structure.ts
index 714adecf217632e6c000e5e2344ff76866148005..b9b623d33ce48996797da7efe367930b6235cc22 100644
--- a/src/mol-plugin/state/actions/structure.ts
+++ b/src/mol-plugin/state/actions/structure.ts
@@ -13,7 +13,7 @@ import { StateTransforms } from '../transforms';
 import { Download } from '../transforms/data';
 import { StructureRepresentation3DHelpers } from '../transforms/representation';
 import { CustomModelProperties, StructureSelection } from '../transforms/model';
-import { DataFormatProvider } from './data-format';
+import { DataFormatProvider, guessCifVariant } from './data-format';
 import { FileInfo } from 'mol-util/file-info';
 import { Task } from 'mol-task';
 import { StructureElement } from 'mol-model/structure';
@@ -24,7 +24,10 @@ export const MmcifProvider: DataFormatProvider<any> = {
     stringExtensions: ['cif', 'mmcif', 'mcif'],
     binaryExtensions: ['bcif'],
     isApplicable: (info: FileInfo, data: Uint8Array | string) => {
-        return info.ext === 'cif' || info.ext === 'mmcif' || info.ext === 'mcif' || info.ext === 'bcif'
+        if (info.ext === 'mmcif' || info.ext === 'mcif') return true
+        // assume cif/bcif files that are not DensityServer CIF are mmCIF
+        if (info.ext === 'cif' || info.ext === 'bcif') return guessCifVariant(info, data) !== 'dscif'
+        return false
     },
     getDefaultBuilder: (ctx: PluginContext, data: StateBuilder.To<PluginStateObject.Data.Binary | PluginStateObject.Data.String>, state: State) => {
         return Task.create('mmCIF default builder', async taskCtx => {
diff --git a/src/mol-plugin/state/actions/volume.ts b/src/mol-plugin/state/actions/volume.ts
index baf6e0ded64d08c380cf907bd4a671302cbeac5a..727114bf9f8b56ec9b7c619130b28e208d79ab06 100644
--- a/src/mol-plugin/state/actions/volume.ts
+++ b/src/mol-plugin/state/actions/volume.ts
@@ -16,7 +16,7 @@ import { PluginStateObject } from '../objects';
 import { StateTransforms } from '../transforms';
 import { Download } from '../transforms/data';
 import { VolumeRepresentation3DHelpers } from '../transforms/representation';
-import { DataFormatProvider } from './data-format';
+import { DataFormatProvider, guessCifVariant } from './data-format';
 
 export const Ccp4Provider: DataFormatProvider<any> = {
     label: 'CCP4/MRC/BRIX',
@@ -59,10 +59,10 @@ export const DscifProvider: DataFormatProvider<any> = {
     description: 'DensityServer CIF',
     stringExtensions: ['cif'],
     binaryExtensions: ['bcif'],
-    isApplicable: (info: FileInfo, data: Uint8Array) => {
-        return info.ext === 'cif' || info.ext === 'bcif'
+    isApplicable: (info: FileInfo, data: Uint8Array | string) => {
+        return guessCifVariant(info, data) === 'dscif' ? true : false
     },
-    getDefaultBuilder: (ctx: PluginContext, data: StateBuilder.To<PluginStateObject.Data.Binary>, state: State) => {
+    getDefaultBuilder: (ctx: PluginContext, data: StateBuilder.To<PluginStateObject.Data.Binary | PluginStateObject.Data.String>, state: State) => {
         return Task.create('DensityServer CIF default builder', async taskCtx => {
             const cifBuilder = data.apply(StateTransforms.Data.ParseCif)
             const cifStateObject = await state.updateTree(cifBuilder).runInContext(taskCtx)