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The Book of Jargon®Oil & Gas

An interactive glossary of acronyms, slang, and industry terminology.

The Book of Jargon® – Oil & Gas is one in a series of practice area and industry-specific glossaries published by Latham & Watkins.

The definitions provide an introduction to each term and may raise complex legal issues on which specific legal advice is required. The terms are also subject to change as applicable laws and customary practice evolve.

This glossary is an essential tool to help readers talk the talk of the oil and gas industry. Drill into this reservoir of terminology.

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The information contained herein is not legal advice and should not be construed as such. 

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Conveyance,Abstract / Abstract of Title,Encumbrance,Mineral Estate,1031 Exchange,Surface Estate,Title Examination,8/8ths / 8/8ths Basis,A&D,AAA,AAPL,AAPL Model Form 610 Joint Operating Agreement (AAPL Form JOA),Abandon / Abandonment,Accommodation Doctrine,Acidizing,Acquisition Agreement,Acquisition Costs,Acquisitions and Divestitures (A&D),Acreage,Acreage Exchange / Acreage Swap / Acreage Trade,Ad Valorem Taxes,Adjusted Purchase Price,Advance Royalty,AFE,After Payout (APO),Aggregate Defect Deductible,AIPN,AIPN Form JOA,AIPN Model Form International Operating Agreement (AIPN Form JOA),Allocated Value,Allowable,American Arbitration Association (AAA),American Association of Petroleum Landmen (AAPL),American Petroleum Institute (API),American Society for Testing and Materials / ASTM International (ASTM),AMI,Ancillary Documents,Annulus,Anticline,API,API Gravity,API Well Number,APO,Appalachian Basin,Appraisal Well,Approved for Development,Aquifer,Area of Mutual Interest (AMI),Arms-Length Transaction,Artificial Lift,As Is, Where Is,Asset Taxes,Assignment and Bill of Sale,Assignment of Production,Associated Gas,Association of International Petroleum Negotiators (AIPN),Assumed Obligations,ASTM,Authority for Expenditure (AFE),Back-In / Back-In Interest,Bakken Shale,Barnett Shale,Barrel (Bbl),Barrel of Oil Equivalent (BOE),Barrel of Oil Equivalent Per Day (BOE/d),Barrel of Oil Per Day / Barrel Per Day (Bopd) (Bbl/d),Base Case,Basin,Bbl/d,Bcf,Bcfe,Beam Pumping,Before Payout (BPO),Behind Pipe,Bell Nipple,BIA,BIA Lease,Billion Cubic Feet (Bcf),Bit,Bitumen,Black Oil,Bleed Off,BLM,BLM Lease,Blowout,Blowout Preventer,Bopd,BOE,BOE/d,BOEM,Bonus,Borehole,Bottomhole Agreement,Bottomhole Assembly,Bottomhole Contribution,Bottomhole Location,Bottomhole Pressure,Brent Crude,Brine,British Thermal Unit (Btu),Btu,Buck the Line Pressure,Burden / Burden on Production,Bureau of Indian Affairs (BIA),Bureau of Land Management (BLM),Bureau of Ocean Energy Management (BOEM),Butane,CA,CAA,Capacity,Capacity Use Agreement,Cap Ex,Capital Expenditures (Cap Ex),Carried Costs / Carry,Carried Interest / Carried Working Interest,Carry Period,Carrying Party,Cash and Carry,Cash Balancing,Cash Call,Casing,Casing String,Casinghead Gas,Casualty Loss,Cat Line,Catwalk,CBM,Cellar,CERCLA,Certificate of Non-Foreign Status,Cessation of Production Clause,CFE,CFIUS,Chain of Title,Christmas Tree,Clean Air Act (CAA),Clean Out Costs,Clean Water Act (CWA),Close / Closing,CO2 Injection,Coalbed Methane (CBM) / Coal Seam Gas,Commencement of Drilling Operations / Commencement of Operations,Commercial Risk,Commercial Well,Commingle,Committee on Foreign Investment in the United States (CFIUS),Communitization,Community Lease,Complete a Well / Completion / Completion Services / Completed,Completion Report,Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA),Compressor / Compressor Station / Compression,Compulsory Pooling / Compulsory Unitization,Condensate,Confidentiality Agreement (CA),Connate Water,Consent,Consenting Party,Conservation,Contingent Resources,Continuation Statement,Continuous Drilling Obligation,Contract Area,Contract Depth,Contract Operating Agreement,Contract Operator,Contribution Agreement,Conventional Drilling,Conventional Reservoirs,Conventional Resources,Convertible Overriding Royalty Interest,COPAS,COPAS Accounting Procedure,Core / Core Sample / Coring,Correlative Interval,Correlative Rights Doctrine,Cost Depletion,Cost Oil,Co-Tenant / Co-Tenancy,Council of Petroleum Accountants Societies (COPAS),Cross-Conveyance / Cross-Assignment,Crude Oil,Cubic Feet Equivalent (CFE),Cumulative Production,Curative Work,Cure Period,Curtailment,Cushing Hub / Cushing, Oklahoma,Customary Post-Closing Consents,Cuttings,CWA,Day Rate Contract,Debtor in Possession (DIP) / DIP Financing,Decline Curve,Decommissioning,Dedicated Area,Dedication,Deed of Trust,Deed of Trust State,Deepening,Default,Defeasible Fee,Defect Claim Date,Defect Deductible,Defensible Title,Dehydration Unit,Delaware Basin,Delay Rental,Delineation Well,Delivery Point,Depletion,Deposit,Depreciation,Depth Severance,Derrick,Derrickman,Designation of Operator Form (DOO),Deterministic v. Probabilistic Reserve Calculation Methods,Developed Acreage,Development / Development Phase,Development Costs,Development Plan,Development Well,Deviated Well,Dip,DIP,Direct Charge,Directional Drilling,Directional Well,Discovered Unrecoverable Resources,Discovery Well,Disposal Well,Dissolved Gas,Division Order / Division of Interest,Dominant Estate,DOO,Down Dip,Downhole,Downstream,Drag-Along Rights,Drainage / Drained,Drainage Area,Drill Bit,Drill Pipe,Drill Ship,Drill String,Drill to Earn,Drilled and Uncompleted (DUC),Driller,Drilling,Drilling Budget,Drilling Carry,Drilling Contractor,Drilling Dollars Structure / Drilling Dollars Target,Drilling Engineer,Drilling Fluid / Drilling Mud,Drilling Fluid Engineer,Drilling Pad,Drilling Permit,Drilling Program,Drilling Report,Drilling Rig,Drilling Unit,Drillsite Title Opinion,Drillsite Tract,Dry Gas,Dry Hole,Dry Hole Contribution,Dry Well,Dual Completion,DUC,Due Diligence,Duster,E&P,Eagle Ford Shale,Earning Trigger,Easement,EBITDA,EBITDAX,Economic Interest,Economically Recoverable Resources,Effective Time,Election Procedures,Elections,Elevator,Endangered and Threatened Species – Endangered Species Act (ESA), Marine Mammal Protection Act (MMPA) and Migratory Bird Treaty Act (MBTA),Engineering, Procurement and Construction (EPC) Contract,Enhanced Oil Recovery (EOR) / Enhanced Recovery,Enhanced Recovery Unit,Entirety Clause,Environmental Condition / Environmental Defect,Environmental Defect Deductible,Environmental Defect Mechanism,Environmental Defect Notice,Environmental Defect Period,Environmental Defect Property,Environmental Defect Threshold,Environmental Indemnity Agreement,Environmental Laws,Environmental Protection Agency (EPA),EOR,EPA,EPC,Escrow Agent,Escrow Agreement,Escrow Fund,Estimated Ultimate Recovery (EUR),Ethane,Excluded Assets,Executive Committee,Executive Right / Executory Right / Executory Interest,Exploitation,Exploration Agreement,Exploration and Production (E&P),Exploration Costs,Exploration Well / Exploratory Well,Extra-Heavy Oil,Electrical Log,Fair Market Value (FMV),Farmee,Farm-In,Farmor,Farmout,Fault,Federal Energy Regulatory Commission (FERC),Federal Exploratory Unit,Federal Lease,Fee Land,Fee Owner Royalty,Fee Simple,Fee Simple Determinable,FERC,Field,Field Rules,Final Settlement Statement,Firm Service,FIRPTA,FIRPTA Certificate,First Purchaser,Fish,Fishing / Fishing Procedures,Flaring,Flow Back,Flow Meter,Flow Rate,Flowing Well,Flowline,Flowline Trap,FL&U,FMV,Force Majeure,Forced Pooling,Foreign Investment in Real Property Tax Act (FIRPTA),Form P-4,Formation,Frac Fluid,Frac Gun,Frac Job,Frac Sand,Frac Stage,Fracking / Fracing,Fractionation / Fractionation Agreement / Processing and Fractionation Agreement,Free Well Agreement,Fuel, Lost, and Unaccounted For (FL&U),Fugitive Emissions,Fundamental Representations,Future Location,Future Well,GAAP,Gas Balancing,Gas Balancing Agreement,Gas Cap,Gas Field,Gas Hydrates,Gas Injection Well,Gas Lift / Gas Lift Drive,Gas Lift Gas,Gas Processing Plant,Gas Well,Gas-Oil Ratio,Gathering,Gathering Agreement,Gathering Line,Gathering System,Gauge Report,Gauger,General Land Office (GLO),General Warranty of Title / General Warranty Deed,Geographic Information System (GIS) Data,Geological and Geophysical (G&G) Data,Geophysical Survey,Geophysicist,Gone to Water,Good and Workmanlike Manner,Good Oilfield Practices,Governmental Section,Grantee,Granting Clause,Grantor,Gross Acres,Groundwater,Gumbo,Gusher,Habendum Clause,Hand,Hard Consent,Hart Scott Rodino Act (HSR Act),Haynesville Shale,Hazardous Substances,HBP,Heads Up / Heads Up Basis,Heater Treater,Heavy Crude Oil,Hedge Contract,Held by Production (HBP),Henry Hub,High Splits,Holdback Amount,Holdback Period,Hookie Dook,Horizon,Horizontal Drainhole Displacement,Horizontal Drilling,Horizontal Spacing,Horizontal Well,Hot Oiler,HSR Act,Hydraulic Fracturing,Hydrocarbons,IDC,IDR,IEA,Imbalances,Impermeable,Implied Covenant,Implied Covenant of Development,Implied Covenant to Prevent Drainage,Improved Oil Recovery (IOR),Incentive Distribution Right (IDR),Increased Density Well,Indemnity Cap,Indemnity De Minimis / Indemnity Threshold,Indemnity Deductible,Independent Landman,Independent Producer / Independent Oil Company,Indian Lands,Individual Defect Threshold,Individual Environmental Defect Threshold,Individual Title Defect Threshold,Industry Player,Infill Well / Infill Drilling,Initial Reservoir Pressure,Initial Shut-In Period,Initial Well,Injection Gas,Injection Well,In-Kind Balancing,In-Situ Recovery,Intangible Drilling and Development Costs (IDCs),Integrated Oil Company,Interconnect Agreement,Interim Period / Interim Period Covenants,Intermediate Crude Oil,Intermittent Gas Lift,International Energy Agency (IEA),Interruptible Service,Interstate Oil and Gas Compact Commission,Jack-Ups / Jack-Up Rig,JDA,Jeffersonian Section,JIB,Joint Account,Joint Development Agreement (JDA),Joint Interest Billing (JIB),Joint Loss Agreement,JOA,Joint Operating Agreement (JOA),Joint Tenancy,Junk,Justified for Development,Kelly,Kelly Bushing,Kick,Kick-Off Point,Kill a Well,Kill Line,LACT,Landman,Landowner,Landowner’s Royalty,Lands,Lateral,Lateral Length,Lay Down Pipe,Lay-Down Spacing Unit v. Stand-Up Spacing Unit,Laying Pipe,Lease,Lease Automatic Custody Transfer (LACT) Unit / LACT Meter,Lease Bonus,Lease Condensate,Lease Exhibit,Lease Operating Expenses (LOE),Lease Tank,Leasehold Assignment,Leasehold Interests,Legal Description / Legal Property Description,Lessee,Lessor,Lessor Royalty,Letter of Credit,Letter of Intent (LOI),Letters in Lieu of Transfer Orders,Lifting Costs,Light Crude Oil,Like-Kind Exchange,Liquefied Natural Gas (LNG),Liquefied Petroleum Gas (LPG),Liquid Hydrocarbons,Liquid-Rich Shales,Live Oil,LNG,Location Exception,LOE,Log,LOI,Losing the Hole,Loss of Title,LPG,Lubricant,MAC,MAE,Mailbox Money,Maintenance of Uniform Interest (MUI),Making Hole,Management Committee,Marcellus Shale,Marginal Well,Marketable Title,Marketing Agreement,Mark-to-Market Accounting,Master Limited Partnership (MLP),Master Services Agreement (MSA),Material Adverse Effect (MAE) / Material Adverse Change (MAC),Material Contracts,Maturation,Mbbl,Mbbl/d,Mboe,Mboe/d,Mcf,Mcfe,Measured Depth,Measuring Tank,Mechanic’s and Materialman’s Lien / M&M Lien,Memorandum of Understanding (MOU),Meridian,Meter,Meter Station,Metes and Bounds,Methane,Midland Basin,Midstream,Migration,Mineral Deed,Mineral Interest,Mineral Lien,Mineral Rights,Minimum Royalty / Minimum Royalty Clause,Minimum Volume Commitment (MVC),Mississippi Lime Shale,MLP,Mmbl,Mmboe,MMBtu,Mmcf,Mobilization,Moonpool,Mortgage,Mortgage State,Mother Hubbard Clause,MOU,Mousehole,MSA,Mud,Mud Engineer / Mud Logger,Mud Gas Separator,MUI,Multilateral Well,Multiple Completions,Multi-Stage Hydraulic Fracturing,MVC,NASDAQ,National Association of Securities Dealers Automated Quotations (NASDAQ),National Environmental Policy Act (NEPA),National Oil Company (NOC),Native Gas,Natural Gas,Natural Gas Liquid (NGL),Natural Gas Policy Act (NGPA),Natural Gasoline,Naturally Flowing Well,Naturally Occurring Radioactive Material (NORM),NDA,NEPA,Net Acres,Net Profits Interest (NPI),Net Revenue Interest (NRI),Net Well,Net Well Structure / Net Well Target,New York Mercantile Exchange (NYMEX),New York Stock Exchange (NYSE),NGL,NGPA,Niobrara Shale,Nipple Down,Nipple Up,NOC,Nodding Donkey,Nomination,Nonassociated Gas,Non-Commercial,Non-Conforming Hydrocarbons,Non-Consent / Non-Consenting Party,Non-Consent Operation / Non-Consent Well,Non-Consent Penalty,Non-Disclosure Agreement (NDA),Non-Operating Working Interests / Non-Operating Interest / Non-Operator / Non-Op,Non-Participating Royalty Interest (NPRI),NORM,Not to be Unreasonably Withheld,NPI,NPRI,NRI,NYMEX,NYSE,Obligation Well / Obligatory Well,Occupational Safety & Health Act,Occupational Safety & Health Administration (OSHA),OCS,OCSLA,OECD,Officer’s Certificate,Off-Ramp,Offset Well,Off-Spec Hydrocarbons,Oil and Gas Lease,Oil and Gas Properties,Oil and Gas Separator,Oil Bank,Oil Field,Oil, Gas and Mineral Lease,Oil Pollution Act (OPA),Oil Pool,Oil Prone,Oil Sands,Oil Well,Oil Zone,Oil-in-Place (OIP),OIP,Oklahoma Corporation Commission,On Production,On the Pump,OPA,Open Flow Potential,Open Formation,Open Hole / Open Hole Completion,Operating Agreement,Operating Committee,Operating Interest / Operating Rights Interest,Operational Flow Order,Operator,Operator’s Lien,Or Lease,Organization for Economic Co-operation and Development (OECD),ORRI,OSHA,Our Watch, Your Watch,Outer Continental Shelf (OCS),Outer Continental Shelf Lands Act (OCSLA),Overage,Overburden,Over-Delivered,Overhead,Over-Produced,Overriding Royalty Interest (ORRI) / Override,P10 / P50 / P90 / PMean,Packer,P&A,Paid-Up Lease,Partial Release,Participating Interest,Participating Parties,Participation Agreement / Participation and Development Agreement,Partition / Partition Rights,Pay Zone,Paying Quantities,Payout,PDP,PDNP,Penetration Point,Pentane,Percentage Depletion,Perforating Gun,Perforation / Perforating,Performance Bond,Permanent School Fund,Permeability,Permitted Encumbrances / Permitted Liens,Permitted Overages,Petroleum Initially in Place (PIIP),Phase I,Phase I Environmental Site Assessment (Phase I),Phase II,Phase II Environmental Site Assessment (Phase II),Pig,PIIP,Pill,Pilot Hole,Pipeline,Pipeline Imbalance,Platform,Play,PLSS,Plug Back,Plugging and Abandonment (P&A) / P&A Liabilities,Pooled Acreage / Pooled Unit,Pooling,Pooling Agreement,Pooling Amendment,Pooling Interval,Pooling Order,Poor Boy,Porosity,Possible Reserves,Possum Belly,Pour Point,PPQ,Preferential Right to Purchase / Pref Right,Preliminary Settlement Statement,Primary Recovery / Primary Production,Primary Term,Priority of Operations,Probable Reserves,Proceeds of Production / Proceeds,Processing / Processing Agreement / Processing and Fractionation Agreement,Produced Water,Producer’s 88,Producer’s Lien,Producing Acreage / Productive Acreage,Producing Formation,Producing Well,Production,Production Costs,Production in Paying Quantities (PPQ) / Production in Commercial Quantities,Production Payment,Production Sharing Contract (PSC),Production Taxes,Production Testing,Production Tubing,Profits à Prendre,Propane,Property Taxes,Proposed Operations,Proppant / Propping Agent,Proration Unit,Prospect,Prospective Resources,Proved Developed Non-Producing Reserves (PDNP),Proved Developed Producing Reserves (PDP),Proved Reserves,Proved Undeveloped Reserves (PUD),PSA,PSC,Public Land Survey System (PLSS),Publicly Traded Partnership,PUD,Pugh Clause,Pumper,Pumping Unit / Pump Jack / Pump,Purchase and Sale Agreement (PSA) / Purchase Agreement,PV-10,Qualifying Income,Quality,Quarter,Quitclaim / Quitclaim Deed,Rail Car,Range,Rate of Penetration,Rathole,RCRA,Reasonable and Prudent Operator (RPO),Reassignment Clause,Recapture,Receipt Point,Recompleting / Recompletion,Record Title,Recording,Recording Memorandum / Recording Supplement,Recoupment,Recovery Factor / Recovery Efficiency,Recycled Gas,Re-enter,Refining,Reid Vapor Pressure (RVP),Release,Relief Well,Relinquishment Act Lands,Relinquishment Provision,Remediation,Remediation Amount,Removal of Operator,Representations and Warranties,Reserve Report,Reserves,Reserves Adjustment Factors,Reserves Growth,Reservoir,Reservoir Drive,Reservoir Engineer / Reservoir Engineering,Reservoir Pressure,Reservoir Rock,Reservoir Stimulation,Residual Oil,Resource Conservation and Recovery Act (RCRA),Resource Play,Resources,Retained Acreage Clause,Retained Liabilities,Retrograde Condensate,Reworking,Rig,Rig Down,Rig Hand,Rig Up,Right of First Offer (ROFO),Right of First Refusal (ROFR),Right-of-Way (ROW),ROFO,ROFR,Rotary Table,Roughneck,Round Trip,Roustabout,ROW,Royalty / Royalty Payment,Royalty Clause,Royalty Interest,RPO,RRC,Rule 37 (Texas),Rule 38 (Texas),Rule of Capture,Run Sheet,Run Ticket,Running Title,RVP,Safe Drinking Water Act,Salt Dome,Saltwater Disposal Well (SWD),Salvable Equipment,Savings Clause,Scf,SEC,Secondary Recovery,Secondary Term,Secondment Agreement,Section,Section-Township-Range (S-T-R),Seismic Data / 2D Seismic / 3D Seismic / 4D Seismic,Seismic Data License,Semi-Submersible Rig,Send-or-Pay,Separator,Service Agreement,Servient Estate,Servitude,Set Back,Severance of Surface and Mineral Estates,Severance Tax,Severed Property,Shale,Shale Gas / Shale Oil,Shale Shaker,Shared Use Agreement,Ship-or-Pay,Shoot a Well,Shooting Rights,Short Trip,Shortfall Credit,Shortfall Fee / Shortfall Payment,Shrinkage,Shut-In Royalty,Shut-In Well,Side Letter,Sidetracking / Sidetrack Operations,Sidewall Coring,Sign and Close,Sit-Down Title Opinion,Society of Petroleum Engineers (SPE),Soft Consent,Sour Crude Oil,Sour Gas,Source Rock,Spacing / Spacing Area / Spacing Unit / Spacing Order,SPE,Special Warranty of Title / Special Warranty Deed,Spot Price,Spud / Spud-In,Squeeze Job,Stack a Rig,Stand of Pipe / Stand,Standard of Care,Stand-By Costs,Stand-Up Title Opinion,State Leases,Steam Flood,Stimulation,Storage Facility,S-T-R,Strategic Player,Stratigraphic Equivalent,Stratum,Strip Price,Stripper Well / Strippers,Structure,Subdivision Lot,Sublease,Subrogation Clause,Subsequent Operations,Subsequently Created Interest,Substitute Acreage,Substitute Well,Successful Efforts Accounting v. Full Cost Accounting,Successor Operator,Sucker-Rod Lift,Superfund Act,Surface Damages,Surface Damages Clause,Surface Location / Surface Hole Location,Surface Rights / Surface Interests,Surface Use Agreement,Surrender Clause,Survey,Suspense Funds,SWD,Sweet Crude Oil,Sweet Gas,Sweet Spot,Tag-Along Rights,Take or Pay,Take Point,Take-in-Kind,Tangible Drilling Costs,Tank Battery,Tank Car,Tank Farm,Target Formation,Tax Partnership,Tax Partnership Agreement,Tcf,Technically Recoverable Resources,Temporary Cessation of Production Clause,Tenancy in Common,Tender,Terminal,Terminus,Tertiary Recovery,Test Well / Testing Operations,Texas Mineral Interest Pooling Act,Texas Railroad Commission (RRC),Texas Two-Step,Thermal Recovery,Third-for-a-Quarter,Tight Formation,Tight Gas,Title Arbitrator,Title Benefit / Title Benefit Mechanism,Title Benefit Notice,Title Curative,Title Defect,Title Defect Amount,Title Defect Deductible,Title Defect Mechanism,Title Defect Notice,Title Defect Period,Title Defect Threshold,Title Diligence,Title Dispute,Title Failure / Title Loss,Title Indemnity Agreement,Title Opinion,Tool Pusher,Top Lease,Total Depth,Total Vertical Depth,Township,Tract,Transfer Order,Transition Services Agreement (TSA),Trap,Treater,Treatment Facility,Trip,Trip In / Tripping In,Trip Out / Tripping Out,True Vapor Pressure (TVP),True Vertical Depth,Trunk Line,TSA,Tubing,Turning to the Right,Turnkey Contract / Turnkey Well,TVP,Type Curve,Type Curve Area,Uniform Commercial Code Financing Statement / UCC Financing Statement / UCC-1 / UCC-3,Unassociated Gas,Unconventional Drilling,Unconventional Resource,Under-Delivered,Underground Gas Storage,Under-Produced,Undeveloped Acreage,Unit / Unitization,Unit Operator,United States Geological Survey (USGS),Unitization Agreement,Unless Lease,Unplugged Well,Unproved Reserves,Up Dip,Upstream,USGS,Utica Shale,Vee-Door,Venting,Vertical Spacing,Vertical Well,Viscosity,Volatile Oil,Volumetric Production Payment (VPP),Voting Provisions,VPP,Warranty Deed,Warranty of Title,Water Drive,Water Flooding,Water Rights Agreement,Water-Oil Ratio,Weighting Up,Well,Well Casing,Well Control,Well Data,Well Exhibit,Well Imbalances,Well Log,Well Pad,Well Shoot,Well Spacing,Wellbore,Wellbore Assignment,Wellhead,West Texas Intermediate (WTI),Wet Gas,Wildcat / Wildcatter,Wildcat Well,Williston Basin,Wiper Trip,Wireline,Woodford Shale,Working Capital,Working Interest (WI),Workover,Workover Rig,Write-Offs,WTI,Zone,Change-in-Control Provisions,AAPL Form JOA,Title Defect Property