diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..7dfcbd1
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,53 @@
+# Contributing
+
+The SheetJS Libraries should be free and clear to use in your projects.  In
+order to maintain that, every contributor must be vigilant.
+
+There have been many projects in the past that have been very lax regarding
+licensing, and we are of the opinion that those are ticking timebombs and that
+no corporate product should depend on them.  
+
+
+# Required Reading
+
+These are pretty short reads and emphasize the importance of proper licensing:
+
+- https://github.com/kennethreitz/tablib/issues/114 (discussion of other tools)
+
+- http://www.codinghorror.com/blog/2007/04/pick-a-license-any-license.html
+
+
+# Pre-Contribution Checklist
+
+Before thinking about contributing, make sure that:
+
+- You are not, nor have ever been, an employee of Microsoft Corporation.
+
+- You have not signed any NDAs or Shared Source Agreements with Microsoft 
+  Corporation or a subsidiary
+
+- You have not consulted any existing relevant codebase (if you have, please
+take note of which codebases were consulted).
+
+If you cannot attest to each of these items, the best approach is to raise an
+issue.  If it is a particularly high-priority issue, please drop an email to
+<sheetjs@gmail.com> and it will be prioritized.
+
+
+# Intra-Contribution
+
+Keep these in mind as you work:
+
+- Your contributions are your original work.  Take note of any resources you
+  consult in the process (and be extra careful not to use unlicensed code on
+  the internet.
+
+- You are working on your own time.  Unless they explicitly grant permission, 
+  your employer may be the ultimate owner of your IP
+
+
+# Post-Contribution 
+
+Before contributions are merged, you will receive an email (at the address
+associated with the git commit) and will be asked to confirm the aforementioned
+items.
diff --git a/README.md b/README.md
index bcfbf0f..3c74a54 100644
--- a/README.md
+++ b/README.md
@@ -43,7 +43,13 @@ Some helper functions in `XLSX.utils` generate different views of the sheets:
 - `XLSX.utils.sheet_to_row_object_array` interprets sheets as tables with a header column and generates an array of objects
 - `XLSX.utils.get_formulae` generates a list of formulae
 
-## Notes
+For more details:
+
+- `bin/xlsx2csv.njs` is a tool for node
+- `index.html` is the live demo
+- `bits/90_utils.js` contains the logic for generating CSV and JSON from sheets
+
+## Cell Object Description 
 
 `.SheetNames` is an ordered list of the sheets in the workbook
 
@@ -52,17 +58,27 @@ that does not start with `!` corresponds to a cell (using `A-1` notation).
 
 `.Sheets[sheetname][address]` returns the specified cell:
 
-- `.v` returns the raw value of the cell
-- `.w` returns the formatted text of the cell
-- `.t` returns the type of the cell (constrained to the enumeration `ST_CellType` as documented in page 4215 of ISO/IEC 29500-1:2012(E) )
+- `.v` : the raw value of the cell
+- `.w` : the formatted text of the cell (if applicable)
+- `.t` : the type of the cell (constrained to the enumeration `ST_CellType` as documented in page 4215 of ISO/IEC 29500-1:2012(E) )
+- `.f` : the formula of the cell (if applicable)
+- `.r` : the rich text encoding of a cell text (if applicable)
+- `.h` : an HTML rendering of the rich text (if applicable)
+- `.c` : comments associated with the cell
+- `.z` : the number format string associated with the cell (if requested) 
 
 For dates, `.v` holds the raw date code from the sheet and `.w` holds the text
 
-For more details:
+## Options
 
-- `bin/xlsx2csv.njs` is a tool for node
-- `index.html` is the live demo
-- `bits/90_utils.js` contains the logic for generating CSV and JSON from sheets
+The exported `read` and `readFile` functions accept an options argument:
+
+| Option Name | Default | Description |
+| :---------- | ------: | :---------- |
+| cellNF      | false   | Save number format string to the .z field |
+| sheetStubs  | true    | Create cell objects for stub cells |
+
+The defaults are enumerated in bits/84_defaults.js 
 
 ## Tested Environments
 
@@ -94,6 +110,10 @@ $ simplehttpserver # or "python -mSimpleHTTPServer" or "serve"
 $ open -a Chromium.app http://localhost:8000/stress.html
 ```
 
+## Contributing
+
+Due to the precarious nature of the Open Specifications Promise, it is very important to ensure code is cleanroom.  Consult CONTRIBUTING.md 
+
 ## XLS Support
 
 XLS is available in [js-xls](https://github.com/SheetJS/js-xls).
diff --git a/bits/31_version.js b/bits/31_version.js
index ede97ea..e573b37 100644
--- a/bits/31_version.js
+++ b/bits/31_version.js
@@ -1 +1 @@
-XLSX.version = '0.5.2';
+XLSX.version = '0.5.3';
diff --git a/bits/57_styxml.js b/bits/57_styxml.js
index 8f057e4..2217411 100644
--- a/bits/57_styxml.js
+++ b/bits/57_styxml.js
@@ -43,7 +43,7 @@ function parseCXfs(t) {
 }
 
 /* 18.8 Styles CT_Stylesheet*/
-function parse_styles(data) {
+function parse_sty_xml(data) {
 	/* 18.8.39 styleSheet CT_Stylesheet */
 	var t;
 
diff --git a/bits/58_stybin.js b/bits/58_stybin.js
index c4c192f..c4b7116 100644
--- a/bits/58_stybin.js
+++ b/bits/58_stybin.js
@@ -14,7 +14,7 @@ function parse_BrtXF(data, length) {
 function parse_sty_bin(data) {
 	styles.NumberFmt = [];
 	for(var y in SSF._table) styles.NumberFmt[y] = SSF._table[y];
-	
+
 	styles.CellXf = [];
 	var state = "";
 	var pass = false;
diff --git a/bits/72_wsxml.js b/bits/72_wsxml.js
index 080df0e..5295de5 100644
--- a/bits/72_wsxml.js
+++ b/bits/72_wsxml.js
@@ -1,5 +1,5 @@
 /* 18.3 Worksheets */
-function parse_worksheet(data) {
+function parse_ws_xml(data, opts) {
 	if(!data) return data;
 	/* 18.3.1.99 worksheet CT_Worksheet */
 	var s = {};
@@ -30,16 +30,19 @@ function parse_worksheet(data) {
 				var cref_cell = decode_cell(cref[1]);
 				idx = cref_cell.c;
 			}
-			if(refguess.s.c > idx) refguess.s.c = idx;
-			if(refguess.e.c < idx) refguess.e.c = idx;
 			var cell = parsexmltag((c.match(/<c[^>]*>/)||[c])[0]); delete cell[0];
 			var d = c.substr(c.indexOf('>')+1);
 			var p = {};
 			q.forEach(function(f){var x=d.match(matchtag(f));if(x)p[f]=unescapexml(x[1]);});
 
 			/* SCHEMA IS ACTUALLY INCORRECT HERE.  IF A CELL HAS NO T, EMIT "" */
-			if(cell.t === undefined && p.v === undefined) { p.t = "str"; p.v = undefined; }
+			if(cell.t === undefined && p.v === undefined) {
+				if(!opts.sheetEmptyCells) return;
+				p.t = "str"; p.v = undefined;
+			}
 			else p.t = (cell.t ? cell.t : "n"); // default is "n" in schema
+			if(refguess.s.c > idx) refguess.s.c = idx;
+			if(refguess.e.c < idx) refguess.e.c = idx;
 			switch(p.t) {
 				case 'n': p.v = parseFloat(p.v); break;
 				case 's': {
@@ -71,7 +74,10 @@ function parse_worksheet(data) {
 				var cf = styles.CellXf[cell.s];
 				if(cf && cf.numFmtId) fmtid = cf.numFmtId;
 			}
-			try { p.w = SSF.format(fmtid,p.v,_ssfopts); } catch(e) { }
+			try {
+				p.w = SSF.format(fmtid,p.v,_ssfopts);
+				if(opts.cellNF) p.z = SSF._table[fmtid];
+			} catch(e) { }
 			s[cell.r] = p;
 		});
 	});
diff --git a/bits/73_wsbin.js b/bits/73_wsbin.js
index f0e7194..5a8411f 100644
--- a/bits/73_wsbin.js
+++ b/bits/73_wsbin.js
@@ -81,14 +81,14 @@ var parse_BrtFmlaBool = parsenoop;
 var parse_BrtFmlaString = parsenoop;
 
 /* [MS-XLSB] 2.1.7.61 Worksheet */
-var parse_ws_bin = function(data) {
+var parse_ws_bin = function(data, opts) {
 	if(!data) return data;
 	var s = {};
 
 	var ref;
 
 	var pass = false;
-	var row, p;
+	var row, p, cf;
 	recordhopper(data, function(val, R) {
 		switch(R.n) {
 			case 'BrtWsDim': ref = val; break;
@@ -115,8 +115,9 @@ var parse_ws_bin = function(data) {
 					case 'str': if(p.v) p.v = utf8read(p.v); break;
 				}
 				if(val[3]) p.f = val[3];
-				if(styles.CellXf[val[0].iStyleRef]) try {
-					p.w = SSF.format(styles.CellXf[val[0].iStyleRef].ifmt,p.v,_ssfopts);
+				if((cf = styles.CellXf[val[0].iStyleRef])) try {
+					p.w = SSF.format(cf.ifmt,p.v,_ssfopts);
+					if(opts.cellNF) p.z = SSF._table[cf.ifmt];
 				} catch(e) { }
 				s[encode_cell({c:val[0].c,r:row.r})] = p;
 				break; // TODO
diff --git a/bits/77_wbxml.js b/bits/77_wbxml.js
index 56bc457..817e2fc 100644
--- a/bits/77_wbxml.js
+++ b/bits/77_wbxml.js
@@ -5,7 +5,7 @@ var XMLNS_WB = [
 ];
 
 /* 18.2 Workbook */
-function parse_workbook(data) {
+function parse_wb_xml(data) {
 	var wb = { AppVersion:{}, WBProps:{}, WBView:[], Sheets:[], CalcPr:{}, xmlns: "" };
 	var pass = false;
 	data.match(/<[^>]*>/g).forEach(function(x) {
diff --git a/bits/79_xmlbin.js b/bits/79_xmlbin.js
index cb9a1e6..3927460 100644
--- a/bits/79_xmlbin.js
+++ b/bits/79_xmlbin.js
@@ -1,11 +1,11 @@
-function parse_wb(data, name) {
-	return name.substr(-4)===".bin" ? parse_wb_bin(data) : parse_workbook(data);
+function parse_wb(data, name, opts) {
+	return name.substr(-4)===".bin" ? parse_wb_bin(data, opts) : parse_wb_xml(data, opts);
 }
 
-function parse_ws(data, name) {
-	return name.substr(-4)===".bin" ? parse_ws_bin(data) : parse_worksheet(data);
+function parse_ws(data, name, opts) {
+	return name.substr(-4)===".bin" ? parse_ws_bin(data, opts) : parse_ws_xml(data, opts);
 }
 
-function parse_sty(data, name) {
-	return name.substr(-4)===".bin" ? parse_sty_bin(data) : parse_styles(data);
+function parse_sty(data, name, opts) {
+	return name.substr(-4)===".bin" ? parse_sty_bin(data, opts) : parse_sty_xml(data, opts);
 }
diff --git a/bits/84_defaults.js b/bits/84_defaults.js
new file mode 100644
index 0000000..17ea03f
--- /dev/null
+++ b/bits/84_defaults.js
@@ -0,0 +1,10 @@
+function fixopts(opts) {
+	var defaults = [
+		['cellNF', false], /* emit cell number format string as .z */
+
+		['sheetStubs', true], /* emit empty cells */
+
+		['WTF', false] /* WTF mode (do not use) */
+	];
+	defaults.forEach(function(d) { if(typeof opts[d[0]] === 'undefined') opts[d[0]] = d[1]; });
+}
diff --git a/bits/85_parsezip.js b/bits/85_parsezip.js
index 7082035..f95cda8 100644
--- a/bits/85_parsezip.js
+++ b/bits/85_parsezip.js
@@ -1,4 +1,6 @@
-function parseZip(zip) {
+function parseZip(zip, opts) {
+	opts = opts || {};
+	fixopts(opts);
 	reset_cp();
 	var entries = Object.keys(zip.files);
 	var keys = entries.filter(function(x){return x.substr(-1) != '/';}).sort();
@@ -40,7 +42,7 @@ function parseZip(zip) {
 			try { /* TODO: remove these guards */
 				path = 'xl/worksheets/sheet' + (i+1) + (xlsb?'.bin':'.xml');
 				relsPath = path.replace(/^(.*)(\/)([^\/]*)$/, "$1/_rels/$3.rels");
-				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path);
+				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path,opts);
 				sheetRels[props.SheetNames[i]]=parseRels(getdata(getzipfile(zip, relsPath)), path);
 			} catch(e) {}
 		}
@@ -50,7 +52,7 @@ function parseZip(zip) {
 				//var path = dir.sheets[i].replace(/^\//,'');
 				path = 'xl/worksheets/sheet' + (i+1) + (xlsb?'.bin':'.xml');
 				relsPath = path.replace(/^(.*)(\/)([^\/]*)$/, "$1/_rels/$3.rels");
-				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path);
+				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path,opts);
 				sheetRels[props.SheetNames[i]]=parseRels(getdata(getzipfile(zip, relsPath)), path);
 			} catch(e) {/*console.error(e);*/}
 		}
diff --git a/bits/88_read.js b/bits/88_read.js
index ce93f59..333a34a 100644
--- a/bits/88_read.js
+++ b/bits/88_read.js
@@ -9,7 +9,7 @@ function readSync(data, options) {
 		case "base64": zip = new jszip(d, { base64:true }); break;
 		case "binary": zip = new jszip(d, { base64:false }); break;
 	}
-	return parseZip(zip);
+	return parseZip(zip, o);
 }
 
 function readFileSync(data, options) {
diff --git a/misc/xl.d.ts b/misc/xl.d.ts
index 25812bb..c699cc1 100644
--- a/misc/xl.d.ts
+++ b/misc/xl.d.ts
@@ -1,7 +1,12 @@
 interface Cell {
   v;
-  t: string;
-  ixfe: number;
+  w?: string;
+  t?: string;
+  f?: string;
+  r?: string;
+  h?: string;
+  c?: any;
+  z?: string;
 }
 
 interface Worksheet {
diff --git a/package.json b/package.json
index abd1b3d..f6bb8a7 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "xlsx",
-	"version": "0.5.2",
+	"version": "0.5.3",
 	"author": "sheetjs",
 	"description": "XLSB / XLSX / XLSM parser",
 	"keywords": [ "xlsx", "xlsb", "xlsm", "office", "excel", "spreadsheet" ],
diff --git a/xlsx.js b/xlsx.js
index 202844f..95da242 100644
--- a/xlsx.js
+++ b/xlsx.js
@@ -420,7 +420,7 @@ SSF.load_table = function(tbl) { for(var i=0; i!=0x0188; ++i) if(tbl[i]) SSF.loa
 make_ssf(SSF);
 var XLSX = {};
 (function(XLSX){
-XLSX.version = '0.5.2';
+XLSX.version = '0.5.3';
 var current_codepage, current_cptable, cptable;
 if(typeof module !== "undefined" && typeof require !== 'undefined') {
 	if(typeof cptable === 'undefined') cptable = require('codepage');
@@ -994,7 +994,7 @@ function parseCXfs(t) {
 }
 
 /* 18.8 Styles CT_Stylesheet*/
-function parse_styles(data) {
+function parse_sty_xml(data) {
 	/* 18.8.39 styleSheet CT_Stylesheet */
 	var t;
 
@@ -1032,7 +1032,7 @@ function parse_BrtXF(data, length) {
 function parse_sty_bin(data) {
 	styles.NumberFmt = [];
 	for(var y in SSF._table) styles.NumberFmt[y] = SSF._table[y];
-	
+
 	styles.CellXf = [];
 	var state = "";
 	var pass = false;
@@ -1301,7 +1301,7 @@ var strs = {}; // shared strings
 var _ssfopts = {}; // spreadsheet formatting options
 
 /* 18.3 Worksheets */
-function parse_worksheet(data) {
+function parse_ws_xml(data, opts) {
 	if(!data) return data;
 	/* 18.3.1.99 worksheet CT_Worksheet */
 	var s = {};
@@ -1332,16 +1332,19 @@ function parse_worksheet(data) {
 				var cref_cell = decode_cell(cref[1]);
 				idx = cref_cell.c;
 			}
-			if(refguess.s.c > idx) refguess.s.c = idx;
-			if(refguess.e.c < idx) refguess.e.c = idx;
 			var cell = parsexmltag((c.match(/<c[^>]*>/)||[c])[0]); delete cell[0];
 			var d = c.substr(c.indexOf('>')+1);
 			var p = {};
 			q.forEach(function(f){var x=d.match(matchtag(f));if(x)p[f]=unescapexml(x[1]);});
 
 			/* SCHEMA IS ACTUALLY INCORRECT HERE.  IF A CELL HAS NO T, EMIT "" */
-			if(cell.t === undefined && p.v === undefined) { p.t = "str"; p.v = undefined; }
+			if(cell.t === undefined && p.v === undefined) {
+				if(!opts.sheetEmptyCells) return;
+				p.t = "str"; p.v = undefined;
+			}
 			else p.t = (cell.t ? cell.t : "n"); // default is "n" in schema
+			if(refguess.s.c > idx) refguess.s.c = idx;
+			if(refguess.e.c < idx) refguess.e.c = idx;
 			switch(p.t) {
 				case 'n': p.v = parseFloat(p.v); break;
 				case 's': {
@@ -1373,7 +1376,10 @@ function parse_worksheet(data) {
 				var cf = styles.CellXf[cell.s];
 				if(cf && cf.numFmtId) fmtid = cf.numFmtId;
 			}
-			try { p.w = SSF.format(fmtid,p.v,_ssfopts); } catch(e) { }
+			try {
+				p.w = SSF.format(fmtid,p.v,_ssfopts);
+				if(opts.cellNF) p.z = SSF._table[fmtid];
+			} catch(e) { }
 			s[cell.r] = p;
 		});
 	});
@@ -1464,14 +1470,14 @@ var parse_BrtFmlaBool = parsenoop;
 var parse_BrtFmlaString = parsenoop;
 
 /* [MS-XLSB] 2.1.7.61 Worksheet */
-var parse_ws_bin = function(data) {
+var parse_ws_bin = function(data, opts) {
 	if(!data) return data;
 	var s = {};
 
 	var ref;
 
 	var pass = false;
-	var row, p;
+	var row, p, cf;
 	recordhopper(data, function(val, R) {
 		switch(R.n) {
 			case 'BrtWsDim': ref = val; break;
@@ -1498,8 +1504,9 @@ var parse_ws_bin = function(data) {
 					case 'str': if(p.v) p.v = utf8read(p.v); break;
 				}
 				if(val[3]) p.f = val[3];
-				if(styles.CellXf[val[0].iStyleRef]) try {
-					p.w = SSF.format(styles.CellXf[val[0].iStyleRef].ifmt,p.v,_ssfopts);
+				if((cf = styles.CellXf[val[0].iStyleRef])) try {
+					p.w = SSF.format(cf.ifmt,p.v,_ssfopts);
+					if(opts.cellNF) p.z = SSF._table[cf.ifmt];
 				} catch(e) { }
 				s[encode_cell({c:val[0].c,r:row.r})] = p;
 				break; // TODO
@@ -1624,7 +1631,7 @@ var XMLNS_WB = [
 ];
 
 /* 18.2 Workbook */
-function parse_workbook(data) {
+function parse_wb_xml(data) {
 	var wb = { AppVersion:{}, WBProps:{}, WBView:[], Sheets:[], CalcPr:{}, xmlns: "" };
 	var pass = false;
 	data.match(/<[^>]*>/g).forEach(function(x) {
@@ -1793,16 +1800,16 @@ var parse_wb_bin = function(data) {
 
 	return wb;
 };
-function parse_wb(data, name) {
-	return name.substr(-4)===".bin" ? parse_wb_bin(data) : parse_workbook(data);
+function parse_wb(data, name, opts) {
+	return name.substr(-4)===".bin" ? parse_wb_bin(data, opts) : parse_wb_xml(data, opts);
 }
 
-function parse_ws(data, name) {
-	return name.substr(-4)===".bin" ? parse_ws_bin(data) : parse_worksheet(data);
+function parse_ws(data, name, opts) {
+	return name.substr(-4)===".bin" ? parse_ws_bin(data, opts) : parse_ws_xml(data, opts);
 }
 
-function parse_sty(data, name) {
-	return name.substr(-4)===".bin" ? parse_sty_bin(data) : parse_styles(data);
+function parse_sty(data, name, opts) {
+	return name.substr(-4)===".bin" ? parse_sty_bin(data, opts) : parse_sty_xml(data, opts);
 }
 /* [MS-XLSB] 2.3 Record Enumeration */
 var RecordEnum = {
@@ -2624,7 +2631,19 @@ var RecordEnum = {
 	0xFFFF: { n:"", f:parsenoop }
 };
 
-function parseZip(zip) {
+function fixopts(opts) {
+	var defaults = [
+		['cellNF', false], /* emit cell number format string as .z */
+
+		['sheetStubs', true], /* emit empty cells */
+
+		['WTF', false] /* WTF mode (do not use) */
+	];
+	defaults.forEach(function(d) { if(typeof opts[d[0]] === 'undefined') opts[d[0]] = d[1]; });
+}
+function parseZip(zip, opts) {
+	opts = opts || {};
+	fixopts(opts);
 	reset_cp();
 	var entries = Object.keys(zip.files);
 	var keys = entries.filter(function(x){return x.substr(-1) != '/';}).sort();
@@ -2666,7 +2685,7 @@ function parseZip(zip) {
 			try { /* TODO: remove these guards */
 				path = 'xl/worksheets/sheet' + (i+1) + (xlsb?'.bin':'.xml');
 				relsPath = path.replace(/^(.*)(\/)([^\/]*)$/, "$1/_rels/$3.rels");
-				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path);
+				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path,opts);
 				sheetRels[props.SheetNames[i]]=parseRels(getdata(getzipfile(zip, relsPath)), path);
 			} catch(e) {}
 		}
@@ -2676,7 +2695,7 @@ function parseZip(zip) {
 				//var path = dir.sheets[i].replace(/^\//,'');
 				path = 'xl/worksheets/sheet' + (i+1) + (xlsb?'.bin':'.xml');
 				relsPath = path.replace(/^(.*)(\/)([^\/]*)$/, "$1/_rels/$3.rels");
-				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path);
+				sheets[props.SheetNames[i]]=parse_ws(getdata(getzipfile(zip, path)),path,opts);
 				sheetRels[props.SheetNames[i]]=parseRels(getdata(getzipfile(zip, relsPath)), path);
 			} catch(e) {/*console.error(e);*/}
 		}
@@ -2708,7 +2727,7 @@ function readSync(data, options) {
 		case "base64": zip = new jszip(d, { base64:true }); break;
 		case "binary": zip = new jszip(d, { base64:false }); break;
 	}
-	return parseZip(zip);
+	return parseZip(zip, o);
 }
 
 function readFileSync(data, options) {