| Class Num. | Count | Class Description |
| 514 | 84573 | Drug, bio-affecting and body treating compositions |
| 435 | 65003 | Chemistry: molecular biology and microbiology |
| 424 | 51709 | Drug, bio-affecting and body treating compositions |
| 428 | 27665 | Stock material or miscellaneous articles |
| 430 | 24033 | Radiation imagery chemistry: process, composition, or product thereof |
| 438 | 19847 | Semiconductor device manufacturing: process |
| 210 | 14934 | Liquid purification or separation |
| 524 | 14883 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 123 | 11950 | Internal-combustion engines |
| 530 | 11712 | Chemistry: natural resins or derivatives; peptides or proteins; lignins or react |
| 257 | 11356 | Active solid-state devices (e.g., transistors, solid-state diodes) |
| 525 | 10826 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 427 | 10761 | Coating processes |
| 73 | 10629 | Measuring and testing |
| 510 | 10437 | Cleaning compositions for solid surfaces, auxiliary compositions therefor, or pr |
| 536 | 10228 | Organic compounds -- part of the class 532-570 series |
| 528 | 9895 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 347 | 9115 | Incremental printing of symbolic information |
| 526 | 8361 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 800 | 8299 | Multicellular living organisms and unmodified parts thereof and related processe |
| 429 | 8147 | Chemistry: electrical current producing apparatus, product, and process |
| 600 | 7617 | Surgery |
| 252 | 7266 | Compositions |
| 426 | 6994 | Food or edible material: processes, compositions, and products |
| 701 | 6823 | Data processing: vehicles, navigation, and relative location |
| 604 | 6668 | Surgery |
| 422 | 6391 | Chemical apparatus and process disinfecting, deodorizing, preserving, or sterili |
| 250 | 6385 | Radiant energy |
| 60 | 6384 | Power plants |
| 106 | 6300 | Compositions: coating or plastic |
| 264 | 5937 | Plastic and nonmetallic article shaping or treating: processes |
| 62 | 5705 | Refrigeration |
| 436 | 5667 | Chemistry: analytical and immunological testing |
| 204 | 5595 | Chemistry: electrical and wave energy |
| 423 | 5550 | Chemistry of inorganic compounds |
| 523 | 5350 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 504 | 5268 | Plant protecting and regulating compositions |
| 340 | 5140 | Communications: electrical |
| 502 | 5084 | Catalyst, solid sorbent, or support therefor: product or process of making |
| 156 | 5033 | Adhesive bonding and miscellaneous chemical manufacture |
| 606 | 4916 | Surgery |
| 324 | 4909 | Electricity: measuring and testing |
| 359 | 4866 | Optical: systems and elements |
| 399 | 4504 | Electrophotography |
| 219 | 4488 | Electric heating |
| 548 | 4477 | Organic compounds -- part of the class 532-570 series |
| 356 | 4093 | Optics: measuring and testing |
| 318 | 4081 | Electricity: motive power systems |
| 549 | 4022 | Organic compounds -- part of the class 532-570 series |
| 546 | 4018 | Organic compounds -- part of the class 532-570 series |
| 568 | 3939 | Organic compounds -- part of the class 532-570 series |
| 361 | 3901 | Electricity: electrical systems and devices |
| 544 | 3781 | Organic compounds -- part of the class 532-570 series |
| 134 | 3727 | Cleaning and liquid contact with solids |
| 205 | 3639 | Electrolysis: processes, compositions used therein, and methods of preparing the |
| 310 | 3639 | Electrical generator or motor structure |
| 29 | 3511 | Metal working |
| 623 | 3437 | Prosthesis (i.e., artificial body members), parts thereof, or aids and accessori |
| 702 | 3403 | Data processing: measuring, calibrating, or testing |
| 521 | 3387 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 345 | 3218 | Computer graphics processing and selective visual display systems |
| 508 | 3181 | Solid anti-friction devices, materials therefor, lubricant or separant compositi |
| 560 | 3085 | Organic compounds -- part of the class 532-570 series |
| 360 | 3073 | Dynamic magnetic information storage or retrieval |
| 137 | 3064 | Fluid handling |
| 385 | 3061 | Optical waveguides |
| 564 | 2950 | Organic compounds -- part of the class 532-570 series |
| 118 | 2890 | Coating apparatus |
| 180 | 2887 | Motor vehicles |
| 382 | 2738 | Image analysis |
| 700 | 2657 | Data processing: generic control systems or specific applications |
| 607 | 2637 | Surgery: light, thermal, and electrical application |
| 166 | 2628 | Wells |
| 8 | 2590 | Bleaching and dyeing; fluid treatment and chemical modification of textiles and |
| 162 | 2516 | Paper making and fiber liberation |
| 562 | 2474 | Organic compounds -- part of the class 532-570 series |
| 451 | 2442 | Abrading |
| 556 | 2428 | Organic compounds -- part of the class 532-570 series |
| 417 | 2392 | Pumps |
| 280 | 2377 | Land vehicles |
| 585 | 2324 | Chemistry of hydrocarbon compounds |
| 95 | 2310 | Gas separation: processes |
| 396 | 2279 | Photography |
| 348 | 2221 | Television |
| 313 | 2172 | Electric lamp and discharge devices |
| 477 | 2156 | Interrelated power delivery controls, including engine control |
| 128 | 2107 | Surgery |
| 358 | 2054 | Facsimile and static presentation processing |
| 148 | 2030 | Metal treatment |
| 522 | 2008 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 244 | 1992 | Aeronautics and astronautics |
| 136 | 1982 | Batteries: thermoelectric and photoelectric |
| 239 | 1972 | Fluid sprinkling, spraying, and diffusing |
| 315 | 1932 | Electric lamp and discharge devices: systems |
| 101 | 1922 | Printing |
| 540 | 1899 | Organic compounds -- part of the class 532-570 series |
| 501 | 1892 | Compositions: ceramic |
| 208 | 1882 | Mineral oils: processes and products |
| 192 | 1875 | Clutches and power-stop control |
| 74 | 1867 | Machine element or mechanism |
| 222 | 1801 | Dispensing |
| 327 | 1780 | Miscellaneous active electrical nonlinear devices, circuits, and systems |
| 372 | 1771 | Coherent light generators |
| 235 | 1758 | Registers |
| 119 | 1727 | Animal husbandry |
| 369 | 1723 | Dynamic information storage or retrieval |
| 117 | 1684 | Single-crystal, oriented-crystal, and epitaxy growth processes; non-coating appa |
| 44 | 1672 | Fuel and related compositions |
| 455 | 1662 | Telecommunications |
| 75 | 1652 | Specialized metallurgical processes, compositions for use therein, consolidated |
| 47 | 1636 | Plant husbandry |
| 558 | 1626 | Organic compounds -- part of the class 532-570 series |
| 554 | 1548 | Organic compounds -- part of the class 532-570 series |
| 52 | 1537 | Static structures (e.g., buildings) |
| 405 | 1511 | Hydraulic and earth engineering |
| 216 | 1501 | Etching a substrate: processes |
| 363 | 1492 | Electric power conversion systems |
| 475 | 1471 | Planetary gear transmission systems or components |
| 349 | 1447 | Liquid crystal cells, elements and systems |
| 4 | 1436 | Baths, closets, sinks, and spittoons |
| 442 | 1410 | Fabric (woven, knitted, or nonwoven textile or cloth, etc.) |
| 370 | 1384 | Multiplex communications |
| 303 | 1380 | Fluid-pressure and analogous brake systems |
| 320 | 1345 | Electricity: battery or capacitor charging or discharging |
| 165 | 1315 | Heat exchange |
| 516 | 1301 | Colloid systems and wetting agents; subcombinations thereof; processes of |
| 242 | 1289 | Winding, tensioning, or guiding |
| 34 | 1288 | Drying and gas or vapor contact with solids |
| 362 | 1248 | Illumination |
| 342 | 1241 | Communications: directive radio wave systems and devices (e.g., radar, radio nav |
| 425 | 1239 | Plastic article or earthenware shaping or treating: apparatus |
| 175 | 1220 | Boring or penetrating the earth |
| 365 | 1213 | Static information storage and retrieval |
| 141 | 1200 | Fluent material handling, with receiver or receiver coacting means |
| 707 | 1186 | Data processing: database and file management or data structures |
| 174 | 1168 | Electricity: conductors and insulators |
| 271 | 1155 | Sheet feeding or delivering |
| 307 | 1151 | Electrical transmission or interconnection systems |
| 709 | 1128 | Electrical computers and digital processing systems: multicomputer data transfer |
| 188 | 1121 | Brakes |
| 330 | 1116 | Amplifiers |
| 588 | 1111 | Hazardous or toxic waste destruction or containment |
| 414 | 1094 | Material or article handling |
| 355 | 1082 | Photocopying |
| 433 | 1069 | Dentistry |
| 65 | 1064 | Glass manufacturing |
| 378 | 1037 | X-ray or gamma ray systems or devices |
| 366 | 1023 | Agitating |
| 53 | 1015 | Package making |
| 99 | 1011 | Foods and beverages: apparatus |
| 507 | 1008 | Earth boring, well treating, and oil field chemistry |
| 400 | 1000 | Typewriting machines |
| 705 | 993 | Data processing: financial, business practice, management, or cost/price determi |
| 503 | 956 | Record receiver having plural interactive leaves or a colorless color former, me |
| 126 | 950 | Stoves and furnaces |
| 439 | 949 | Electrical connectors |
| 290 | 944 | Prime-mover dynamo plants |
| 15 | 935 | Brushing, scrubbing, and general cleaning |
| 209 | 929 | Classifying, separating, and assorting solids |
| 241 | 917 | Solid material comminution or disintegration |
| 198 | 891 | Conveyors: power-driven |
| 440 | 891 | Marine propulsion |
| 323 | 881 | Electricity: power supply or regulation systems |
| 473 | 881 | Games using tangible projectile |
| 43 | 867 | Fishing, trapping, and vermin destroying |
| 96 | 862 | Gas separation: apparatus |
| 379 | 860 | Telephonic communications |
| 431 | 838 | Combustion |
| 343 | 829 | Communications: radio wave antennas |
| 374 | 827 | Thermal measuring and testing |
| 296 | 794 | Land vehicles: bodies and tops |
| 570 | 794 | Organic compounds -- part of the class 532-570 series |
| 415 | 787 | Rotary kinetic fluid motors or pumps |
| 228 | 786 | Metal fusion bonding |
| 384 | 777 | Bearings |
| 251 | 777 | Valves and valve actuation |
| 206 | 775 | Special receptacle or package |
| 392 | 771 | Electric resistance heating devices |
| 534 | 767 | Organic compounds -- part of the class 532-570 series |
| 81 | 742 | Tools |
| 110 | 740 | Furnaces |
| 164 | 731 | Metal founding |
| 261 | 723 | Gas and liquid contact apparatus |
| 138 | 722 | Pipes and tubular conduits |
| 114 | 717 | Ships |
| 713 | 703 | Electrical computers and digital processing systems: support |
| 72 | 694 | Metal deforming |
| 71 | 680 | Chemistry: fertilizers |
| 375 | 671 | Pulse or digital communications |
| 552 | 666 | Organic compounds -- part of the class 532-570 series |
| 33 | 661 | Geometrical instruments |
| 220 | 652 | Receptacles |
| 55 | 641 | Gas separation |
| 710 | 632 | Electrical computers and digital data processing systems: input/output |
| 445 | 610 | Electric lamp or space discharge component or device manufacturing |
| 248 | 587 | Supports |
| 285 | 575 | Pipe joints or couplings |
| 518 | 574 | Chemistry: fischer-tropsch processes; or purification or recovery of products th |
| 341 | 572 | Coded data generation or conversion |
| 464 | 571 | Rotary shafts, gudgeons, housings, and flexible couplings for rotary shafts |
| 474 | 567 | Endless belt power transmission systems or components |
| 714 | 564 | Error detection/correction and fault detection/recovery |
| 51 | 553 | Abrasive tool making process, material, or composition |
| 401 | 551 | Coating implements with material supply |
| 277 | 549 | Seal for a joint or juncture |
| 236 | 546 | Automatic temperature and humidity regulation |
| 463 | 541 | Amusement devices: games |
| 367 | 536 | Communications, electrical: acoustic wave systems and devices |
| 416 | 525 | Fluid reaction surfaces (i.e., impellers) |
| 434 | 524 | Education and demonstration |
| 706 | 519 | Data processing: artificial intelligence |
| 56 | 519 | Harvesters |
| 152 | 509 | Resilient tires and wheels |
| 203 | 504 | Distillation: processes, separatory |
| 297 | 503 | Chairs and seats |
| 482 | 502 | Exercise devices |
| 351 | 495 | Optics: eye examining, vision testing and correcting |
| 418 | 493 | Rotary expansible chamber devices |
| 149 | 490 | Explosive and thermic compositions or charges |
| 122 | 490 | Liquid heaters and vaporizers |
| 432 | 480 | Heating |
| 237 | 468 | Heating systems |
| 454 | 467 | Ventilation |
| 83 | 462 | Cutting |
| 703 | 461 | Data processing: structural design, modeling, simulation, and emulation |
| 602 | 458 | Surgery: splint, brace, or bandage |
| 446 | 456 | Amusement devices: toys |
| 381 | 439 | Electrical audio signal processing systems and devices |
| 331 | 435 | Oscillators |
| 68 | 430 | Textiles: fluid treating apparatus |
| 102 | 424 | Ammunition and explosives |
| 333 | 421 | Wave transmission lines and networks |
| 200 | 417 | Electricity: circuit makers and breakers |
| 398 | 416 | Optical communications |
| 493 | 415 | Manufacturing container or tube from paper; or other manufacturing from a sheet |
| 84 | 400 | Music |
| 338 | 396 | Electrical resistors |
| 368 | 395 | Horology: time measuring systems or devices |
| 505 | 388 | Superconductor technology: apparatus, material, process |
| 266 | 386 | Metallurgical apparatus |
| 711 | 379 | Electrical computers and digital processing systems: memory |
| 2 | 378 | Apparel |
| 5 | 374 | Beds |
| 419 | 374 | Powder metallurgy processes |
| 404 | 371 | Road structure, process, or apparatus |
| 132 | 361 | Toilet |
| 326 | 360 | Electronic digital logic circuitry |
| 411 | 359 | Expanded, threaded, driven, headed, tool-deformed, or locked-threaded fastener |
| 704 | 352 | Data processing: speech signal processing, linguistics, language translation, an |
| 273 | 341 | Amusement devices: games |
| 169 | 340 | Fire extinguishers |
| 335 | 339 | Electricity: magnetically operated switches, magnets, and electromagnets |
| 403 | 329 | Joints and connections |
| 49 | 328 | Movable or removable closures |
| 452 | 318 | Butchering |
| 267 | 316 | Spring devices |
| 111 | 315 | Planting |
| 100 | 312 | Presses |
| 221 | 312 | Article dispensing |
| 131 | 306 | Tobacco |
| 70 | 304 | Locks |
| 92 | 301 | Expansible chamber devices |
| 187 | 299 | Elevator, industrial lift truck, or stationary lift for vehicle |
| 177 | 299 | Weighing scales |
| 376 | 291 | Induced nuclear reactions: processes, systems, and elements |
| 181 | 288 | Acoustics |
| 48 | 282 | Gas: heating and illuminating |
| 202 | 281 | Distillation: apparatus |
| 512 | 281 | Perfume compositions |
| 40 | 278 | Card, picture, or sign exhibiting |
| 322 | 276 | Electricity: single generator systems |
| 16 | 271 | Miscellaneous hardware |
| 160 | 268 | Flexible or portable closure, partition, or panel |
| 127 | 267 | Sugar, starch, and carbohydrates |
| 716 | 267 | Data processing: design and analysis of circuit or semiconductor mask |
| 30 | 262 | Cutlery |
| 294 | 261 | Handling: hand and hoist-line implements |
| 172 | 260 | Earth working |
| 601 | 260 | Surgery: kinesitherapy |
| 215 | 250 | Bottles and jars |
| 717 | 247 | Data processing: software development, installation, and management |
| 494 | 246 | Imperforate bowl: centrifugal separators |
| 37 | 245 | Excavating |
| 89 | 244 | Ordnance |
| 386 | 241 | Television signal processing for dynamic recording or reproducing |
| 194 | 235 | Check-actuated control mechanisms |
| 104 | 228 | Railways |
| 712 | 227 | Electrical computers and digital processing systems: processing architectures an |
| 408 | 226 | Cutting by use of rotating axially moving tool |
| 91 | 225 | Motors: expansible chamber type |
| 476 | 225 | Friction gear transmission systems or components |
| 173 | 224 | Tool driving or impacting |
| 57 | 223 | Textiles: spinning, twisting, and twining |
| 36 | 222 | Boots, shoes, and leggings |
| 420 | 221 | Alloys or metallic compositions |
| 292 | 218 | Closure fasteners |
| 184 | 216 | Lubrication |
| 144 | 212 | Woodworking |
| 254 | 207 | Implements or apparatus for applying pushing or pulling force |
| 409 | 206 | Gear cutting, milling, or planing |
| 112 | 204 | Sewing |
| 353 | 203 | Optics: image projectors |
| 336 | 193 | Inductor devices |
| 105 | 176 | Railway rolling stock |
| 373 | 173 | Industrial electric heating furnaces |
| 82 | 167 | Turning |
| 139 | 164 | Textiles: weaving |
| 229 | 159 | Envelopes, wrappers, and paperboard boxes |
| 708 | 158 | Electrical computers: arithmetic processing and calculating |
| 715 | 156 | Data processing: presentation processing of document, operator interface process |
| 725 | 156 | Interactive video distribution systems |
| 124 | 156 | Mechanical guns and projectors |
| 406 | 152 | Conveyors: fluid current |
| 312 | 151 | Supports: cabinet structure |
| 270 | 150 | Sheet-material associating |
| 24 | 148 | Buckles, buttons, clasps, etc. |
| 211 | 146 | Supports: racks |
| 108 | 146 | Horizontally supported planar surfaces |
| 19 | 137 | Textiles: fiber preparation |
| 301 | 136 | Land vehicles: wheels and axles |
| 226 | 133 | Advancing material of indeterminate length |
| 42 | 133 | Firearms |
| 246 | 128 | Railway switches and signals |
| 227 | 125 | Elongated-member-driving apparatus |
| 269 | 125 | Work holders |
| 299 | 123 | Mining or in situ disintegration of hard material |
| 472 | 118 | Amusement devices |
| 283 | 118 | Printed matter |
| 380 | 118 | Cryptography |
| 279 | 115 | Chucks or sockets |
| 492 | 115 | Roll or roller |
| 125 | 113 | Stone working |
| 23 | 112 | Chemistry: physical processes |
| 66 | 111 | Textiles: knitting |
| 337 | 107 | Electricity: electrothermally or thermally actuated switches |
| 116 | 107 | Signals and indicators |
| 224 | 104 | Package and article carriers |
| 28 | 103 | Textiles: manufacturing |
| 383 | 103 | Flexible bags |
| 212 | 101 | Traversing hoists |
| 388 | 100 | Electricity: motor control systems |
| 182 | 99 | Fire escape, ladder, or scaffold |
| 453 | 95 | Coin handling |
| 441 | 93 | Buoys, rafts, and aquatic devices |
| 718 | 87 | Electrical computers and digital processing systems: virtual machine task or pro |
| 377 | 83 | Electrical pulse counters, pulse dividers, or shift registers: circuits and syst |
| 218 | 79 | High-voltage switches with arc preventing or extinguishing devices |
| 352 | 79 | Optics: motion pictures |
| 460 | 79 | Crop threshing or separating |
| 135 | 70 | Tent, canopy, umbrella, or cane |
| 346 | 70 | Recorders |
| 407 | 69 | Cutters, for shaping |
| 527 | 69 | Synthetic resins or natural rubbers -- part of the class 520 series |
| 719 | 67 | Electrical computers and digital processing systems: interprogram communication |
| 412 | 66 | Bookbinding: process and apparatus |
| 293 | 63 | Vehicle fenders |
| 178 | 62 | Telegraphy |
| 159 | 61 | Concentrating evaporators |
| 305 | 61 | Wheel substitutes for land vehicles |
| 483 | 58 | Tool changing |
| 38 | 57 | Textiles: ironing or smoothing |
| 410 | 54 | Freight accommodation on freight carrier |
| 332 | 54 | Modulators |
| 140 | 54 | Wireworking |
| 256 | 49 | Fences |
| 191 | 49 | Electricity: transmission to vehicles |
| 225 | 49 | Severing by tearing or breaking |
| 249 | 46 | Static molds |
| 86 | 40 | Ammunition and explosive-charge making |
| 223 | 39 | Apparel apparatus |
| 201 | 38 | Distillation: processes, thermolytic |
| 193 | 38 | Conveyors, chutes, skids, guides, and ways |
| 298 | 35 | Land vehicles: dumping |
| 26 | 34 | Textiles: cloth finishing |
| 76 | 33 | Metal tools and implements, making |
| 14 | 31 | Bridges |
| 232 | 30 | Deposit and collection receptacles |
| 7 | 29 | Compound tools |
| 470 | 28 | Threaded, headed fastener, or washer making: process and apparatus |
| 449 | 28 | Bee culture |
| 402 | 25 | Binder device releasably engaging aperture or notch of sheet |
| 54 | 25 | Harness for working animal |
| 27 | 25 | Undertaking |
| 186 | 24 | Merchandising |
| 450 | 23 | Foundation garments |
| 185 | 23 | Motors: spring, weight, or animal powered |
| 168 | 23 | Farriery |
| 260 | 23 | Chemistry of carbon compounds |
| 213 | 22 | Railway draft appliances |
| 281 | 20 | Books, strips, and leaves |
| 329 | 20 | Demodulators |
| 157 | 17 | Wheelwright machines |
| 238 | 16 | Railways: surface track |
| 87 | 15 | Textiles: braiding, netting, and lace making |
| 12 | 14 | Boot and shoe making |
| 109 | 14 | Safes, bank protection, or a related device |
| 413 | 13 | Sheet metal container making |
| 196 | 13 | Mineral oils: apparatus |
| 300 | 12 | Brush, broom, and mop making |
| 63 | 11 | Jewelry |
| 59 | 10 | Chain, staple, and horseshoe making |
| 171 | 10 | Unearthing plants or buried objects |
| 150 | 8 | Purses, wallets, and protective covers |
| 289 | 6 | Knots and knot tying |
| 69 | 6 | Leather manufactures |
| 190 | 5 | Trunks and hand-carried luggage |
| 295 | 5 | Railway wheels and axles |
| 234 | 3 | Selective cutting (e.g., punching) |
| 142 | 3 | Wood turning |
| 291 | 3 | Track sanders |
| 334 | 3 | Tuners |
| 462 | 2 | Books, strips, and leaves for manifolding |
| 79 | 2 | Button making |
| 258 | 2 | Railway mail delivery |